AU2008200075B1

AU2008200075B1 - Alarm device

Info

Publication number: AU2008200075B1
Application number: AU2008200075A
Authority: AU
Inventors: Michael Ooi
Original assignee: PSA PRODUCTS Pty Ltd
Current assignee: PSA PRODUCTS Pty Ltd
Priority date: 2008-01-08
Filing date: 2008-01-08
Publication date: 2009-06-11
Anticipated expiration: 2028-01-08

Description

AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT ORIGINAL Applicant(s): PSA PRODUCTS PTY LTD Actual Inventor(s): MICHAEL 001 Address for Service: PATENT ATTORNEY SERVICES 26 Ellingworth Parade Box Hill Victoria 3128 Australia Title; ALARM DEVICE Associated Provisional Applications: No(s).: The flowing statement is a full description of this invention, including the best method Of Performing it known to me/us:- 1 ALARM DEVICE Field of the Invention The present application relates to a device for detecting and/or warning of the presence of smoke in a building, and in particular, to a two-part device configured to be relatively easy mounted/detached to the building. 5 Background of the Invention Smoke detectors/alarms are typically devices positioned within or around a building structure to detect the presence of smoke and to issue an alarm to alert people in the immediate area of the presence of a fire or other hazardous situation. In many 10 countries, such as Australia, the provision of smoke alarms in buildings is compulsory and legislation is established to ensure that the installation of smoke alarms is performed to an appropriate standard. In residential dwellings, smoke alarms are intended to detect smoke before it reaches the sleeping occupants of the building, and as such, the reliability and positioning of the smoke alarm/detector is paramount to 15 performing this function. Most conventional smoke detectors employ sensors to detect the presence of smoke. Some devices may employ optical (photoelectric) sensors, chemical sensors that undergo a chemical reaction (ionisation) in the presence of smoke, and in some instances, both types of sensors may be employed to increase sensitivity of the device 20 to detecting the presence of smoke. The sensors typically activate an. alarm that emits an audible warning signal and/or visual signals such as warning lights and the like. In order to function in such a manner, the device must be supplied with electrical power. To ensure reliability of the device, the power supplied to the device must be from a reliable source such that the device can operate even in the event of 25 power supply to a building being disconnected or cut-off. More recently, for residential dwellings it is required that the smoke detectors/alarms be connected to the power mains of the building and carry an auxiliary power supply, in the form of batteries or the like. Such an arrangement ensures that in the event of the power mains supply to the building being disconnected, the device can still draw the power needs from the 30 auxiliary power source for continued operation. In older dwellings, solely battery powered smoke detectors/alarms can employed. In either of these arrangements, in order to ensure that the smoke detector/alarm is operational under a variety of conditions, it is necessary to replace the batteries at regular intervals and to conduct regular tests and maintenance of the device. c:\documents and setfjnosadministratormv doctments\smokedetectorxdoc 2 As smoke rises, most smoke detectors/alarms are installed 'on or near the ceiling of the building, with care taken to avoid installing the device in dead air spaces, which may prevent smoke entrained in air from reaching the device. As such, smoke 5 detectors/alarms are typically installed in difficult to access areas, which require individuals to employ ladders and the like to access the device to change the batteries of the device or perform regular maintenance checks of the device. Most existing smoke detectors comprise two parts, a base portion mounted to the building on or near the ceiling, and a body portion mounted to the base portion which 1o houses the components of the device (including the batteries). The base portion typically includes a cover that can be hinged open to facilitate access to the various components of the device for servicing and changing the batteries. As the device is typically mounted adjacent the ceiling of the building, an individual servicing the device typically requires considerable dexterity to open the cover of the device to perform such maintenance. Duc 15 to the height at which this is often performed, maintenance can be dangerous task, as step ladders and stools are frequent causes of home accidents. This can result in the device not being serviced or maintained at regular intervals. There is a need to provide a smoke detector/alarm that can be relatively easily attached and detached to the building to facilitate servicing of the device in a safe and 20 efficient manner. Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is solely for the purpose of providing a context for the present invention. It is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in the 25 field relevant to the present invention as it existed before the priority date of each claim of this application. Summary of the Invention 30 The present invention provides an alarm device having: a base mountable to a wall or ceiling and having a first contact surface; a body including a housing within which operational components of the device are contained with said components including at least a sensor device and an alarm, said body having a second contact surface; and 35 a single mounting projection on either the base or the body and a corresponding mounting recess on either the body or the base respectively; 3 wherein the mounting projection comprises an elongate portion projecting from the contact surface of the respective base or body and extending along that contact surface from a periphery thereof, and 5 wherein the mounting recess comprises an elongate recess having a mouth opening at a periphery of the contact surface of the respective body or base and from which the elongate recess extends along that contact surface; wherein the body is detachably mounted to the base by a lateral sliding engagement of the first and second contact surfaces across each other so that the mounting projection 0 is laterally slidingly received in the complementary mounting recess and the body is completely detachable from the base by lateral sliding movement only to effect disengagement of the mounting projection and complementary mounting recess. Preferably the elongate portion is defining a central ridge extending generally diametrically from the periphery of the respective contact surface and across a major I5 proportion of the diametrical width of the respective base or body. Preferably the elongate portion has an enlarged head at an end thereof which is proximal to the periphery of the respective contact surface, and wherein the mouth of the elongate mounting recess is enlarged relative to the remainder of the length of the elongate recess so as to receive the enlarged head of the elongate portion during a final 20 stage of the lateral sliding engagement of the body with the base. One or more retaining members may be provided on either the base or the body to engage with the mounting projection to retain the body in position with respect to the base. The one or more retaining members may be clip members located within the mounting recess. 25 In one embodiment, the first contact surface comprises one or more electrical terminals in electrical connection with a remote power source. The remote power source may be a mains power source of a building. In this embodiment, the second contact surface may comprise one or more electrical terminals which engage with the one or more electrical terminals of the first contact surface when the body is mounted to the 30 base to supply power to the operational components of the device from the remote power source. In another embodiment, the body comprises a power source for powering the operational components of the device. In this embodiment, the power source may be one or more batteries. The batteries may be replaced at regular intervals as required by the 35 device.

3a Throughout this specification the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of 5 any other element, integer or step, or group of elements, integers or steps. Brief Description of the Drawings By way of example only, the invention is now described with reference to the accompanying drawings: 4 FIG. 1 shows a plan view of an embodiment of the smoke detector/alarm device of the present invention; FIG. 2 shows a side view of the device of FIG. 1; FIG. 3 shows a top perspective view of the device of FIG. 1 with the base 5 portion and the body portion arranged for assembly; FIG. 4 shows a perspective view of the base portion of the device of FIG. 1, in isolation; FIG. 5 shows a top perspective view of the base portion and the body portion of the device partially detached; and 10 FIG. 6 shows a top perspective view of device of FIG. 1. Detailed Description of an Exemplary Embodiment of the Invention The present invention will be described in relation to a smoke detector/alarm that detects the presence of smoke in air and emits a warning signal accordingly. 15 However, it will be appreciated by those skilled in the art that the present invention could be equally applied for use with a variety of ceiling/wall mounted alarm devices, such as proximity security alarms and air quality detectors which house sensors, control circuitry, batteries and the like. It will also be appreciated that the present invention could be applied to other two-part electrical devices that require detachment of one part 20 of the device for maintenance and the like One embodiment of a smoke detector/alarm device 10 in accordance with the present invention is shown in the accompanying Figures. As shown in FIG. 2, the device 10 comprises a base 12 and a body 18 assembled together to form a single unit. The base 12 is a substantially flat plate element that is 25 secured to a ceiling 8 of a building. The body 18 is a disc-shaped element that houses the operational components of the device 10, such as a sensor, sensor control circuit, auxiliary power source and the like, and is configured to engage with the base 12 such that the body 18 can be securely suspended from the ceiling 8. It will be appreciated that, whilst not shown, the base 12 may alternatively be secured to a wall of a building 30 such that the device 10 is located vertically on the wall. Referring to FIGS. 3 - 5, various views of the base 12 are shown. In general, the base 12 compriscs a backing surface 11 that is configured to abut against a surface of the ceiling or wall, and a facing or contact surface 13 to which the body 18 is mounted. A plurality of apertures 14 are provided through base 12 to facilitate 35 fastening of the base 12 to the ceiling or wall. The apertures 14 are provided to eAdocuments and settinas\administrator\my documents\smokedetector.doc 5 accommodate fastening elements, such as screws, although other fastening means are also envisaged for securing the base 12 to the wall/ceiling The backing surface 11 has a recess 15 formed therein to accommodate a mains power cable (not shown) that provides power to the device 10 when in use. The recess 5 15 includes a covered portion 16 into which the mains power cable is inserted. The covered portion 16 houses a terminal block (not shown) having electrical connection terminals incorporated therein. The electrical connection terminals facilitate electrical connection of the device 10 to the mains power cable such that device 10 is able to operate under power supplied from the mains power of the building. In this 10 arrangement, prior to securing the base 12 to the ceiling of the building, the mains power cable is connected to the terminal block of the covered portion 16 by an appropriate tradesperson. The facing surface 13 of the base 12 is shown in FIG. 4. An elongate projection 21 is provided on the facing surface 13 to define a central ridge extending along the 15 facing surface 13. As shown, the elongate projection 21 is substantially rectangular in cross-section, although other configurations are also envisaged. The elongate projection 21 has a head portion 22 located at a distal end thereof, proximal the periphery of the facing surface 13. The head portion 22 projects from the facing surface 13 a greater distance than the elongate projection 21 and has a width greater 20 than the elongate projection 21. At the junction between the head portion 22 and the elongate projection 21 a plurality of terminals 17 are provided. Terminals 17 are in the form of terminal pins that project from the facing surface 13 and which are in electrical communication with the mains power cable located in the covered portion 16 of the backing surface 11 by 25 way of wires housed within the head portion 22. This arrangement allows for mains power to be supplied to the components of the device housed within the body 18 of the device 10, when the body 18 is assembled to the base 12. The manner in which power transfer between the base 12 and the body 18 is achieved will be described in more detail below. 30 Referring to FIG. 2, the body 18 comprises two main parts, a rear support 20 and a front cover 19. The rear support 20 is configured to engage with the base 12 to secure the body 18 to the ceiling in the manner as shown. The rear support 20 is in the form of a receptacle into which the various operational components of the device 10 are contained, such as the sensor, sensor circuitry, alarm bell, etc. The front cover 19 is 35 fitted over the rear support 20 so as to enclose the components of the device within the rcar support 20. c:\documents and settinas\admnistrator\mv documents\smokedeector.doc 6 Referring to FIG. 1, the front cover 19 forms the external surface of the device 10 when the base 12 and body 18 are assembled together. The surface of the cover 19 contains a test button 25 that can be depressed to test the functionality of the device 10 once assembled, without requiring detachment of the body 18 from the base 12. A pair 5 of LEDs 26 are also provided on the cover 18 to provide a visual indication of the alarm when activated, and to also provide a visual indication of the power status of the device. In this regard, in the event of the device detecting the presence of smoke and activating the alarm accordingly, the alarm LED may flash or otherwise activate to provide a visual indication of the activation of the alarm. The power LED may be 10 activated when the device 10 is receiving power from the mains power supply, and may flash when the auxiliary battery supply is powering the device. In such an arrangement, a user can readily see the power status of the unit. Hence, if the power LED is not activated, this can be an indication that the device is without sufficient power to operate and requires maintenance. 15 The front cover 19 also includes an alarm vent 27 which is located adjacent the bell or alarm emitting component of the device. The vent 27 provide a passage for the sound waves to exit the body 18, thereby ensuring that the alarm signal is audible when activated. As shown more clearly in FIGS. 3, 5 and 6, circumferential vents 28 are 20 provided around the circumference of the front cover 19 to enable air to freely penetrate into the body 18. This arrangement enables the sensor to detect the presence of smoke within the air surrounding the device 10 such that the alarm can be activated accordingly. As shown in FIG. 3, the underside or contact surface of the rear support 20 is 25 shaped to conform to the facing surface 13 of the base 12. In this regard, the underside of the rear support 20 comprises an elongate recess 31 centrally disposed therein. The recess 31 is configured to slidingly receive the elongate projection 21 formed on the facing surface 13 of the base 12. The length of recess 31 is substantially equivalent to the length of the projection 21. A recessed mouth 32 is also formed in the underside of 30 the rear support 20 to accommodate the head portion 22 of the elongate projection 21. The mouth 32 includes a pair of clips 33 provided on opposing sidewalls thereof. Clips 33 assist in guiding the projection 21 into the recess 31 to aid in inserting the body 18 into the base 12. The clips 33 may also be received within grooves (not shown) formed in the head portion 22 of the elongate projection 21 to aid in gripping/retaining the 35 body 18 in position against the base 12. documents and settings\administrator\mV documents\smokedetector.doc 7 As shown in FIG. 3, the body 18 and the base 12 are assembled by sliding the body 18 across the base 12 such that the recess 31 engages with and receives the projection 21. By providing such a sliding motion, the head portion 22 of the base 12 is received within the mouth 32 and the clips 33 engage with the head portion 22 to grip 5 the body 18 against the base 12. Whilst not shown, the recess 31 may also or alternatively have a lip formed around an upper region thereof that receives a rib (not shown) formed along the longitudinally extending sides of the projection 21 to locate and retain the body 18 against the base 12. Other arrangements for gripping and retaining the body 18 against the base 12 are also envisaged. Such arrangements may 10 include a variety of projections/retaining members and corresponding recesses provided on the respective contacting surfaces of the body 18 and base 12 that align together and inter-engage upon sliding contact between the body 18 and base 12. Female electric terminals 35, in the form of terminal sockets, are provided on the rear support 20 at the junction between the mouth 32 and the recess 31. In this 15 arrangement, when the body 18 is slid into engagement with the base 12, the terminal pins 17 provided on the facing surface 13 are received within the electric terminals or sockets 35. This facilitates electrical connection between the base 12 and the body 18 such that mains power can be supplied to the body 18 from the base 12 to power the components contained therein. It will be appreciated that other arrangements for 20 forming the electrical connection between the body 18 and the base 12 are also envisaged. Such arrangements may include flexible/resilient leaf terminals that are positioned on the body 18 and/or base 12 such that they are brought into contact when the body 18 and base 12 are brought into sliding contact. As is shown in FIG. 3, the body 18 also comprises a battery compartment 34 25 that is formed in the underside of the rear support 20 for receiving one or more batteries. The batteries may function as an auxiliary or primary power source for the components of the device 10. In this regard, the device 10 can be used in circumstances where mains power is not available, as well as in circumstances where mains power is available, with the battery power forming a back-up function should the 30 mains power supply be disconnected from the device 10. According to the present invention, it will be appreciated that in order to change the batteries and/or service the device 10, the body 18 can be easily slid in the direction of the arrows (FIG. 5) to become completely detached from the base 12. A user can then remove the body 18 and service the components in the body 18 at a remote and 35 safe location without fear of falling from a dangerous height. This overcomes the problems associated with existing devices, which typically require a user to perform the c:\documents and settInasadminstrator\mv documents\smokedetector.doc 8 necessary service atop a ladder or the like, greatly increasing the chances of the user falling from a height and injuring themselves. It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific S embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive. c:docurnents and settinasadministtormv documentsamokedetector.doc

Claims

1. An alarm device having: 5 a base mountable to a wall or ceiling and having a first contact surface; a body including a housing within which operational components of the device are contained with said components including at least a sensor device and an alarm, said body having a second contact surface; and a single mounting projection on either the base or the body and a corresponding 10 mounting recess on either the body or the base respectively; wherein the mounting projection comprises an elongate portion projecting from the contact surface of the respective base or body and extending along that contact surface from a periphery thereof, and wherein the mounting recess comprises an elongate recess having a mouth opening 15 at a periphery of the contact surface of the respective body or base and from which the elongate recess extends along that contact surface; wherein the body is detachably mounted to the base by a lateral sliding engagement of the first and second contact surfaces across each other so that the mounting projection is laterally slidingly received in the complementary mounting 20 recess and the body is completely detachable from the base by lateral sliding movement only to effect disengagement of the mounting projection and complementary mounting recess,

2. An alarm device according to claim 1 wherein the elongate portion is defining a 25 central ridge extending generally diametrically from the periphery of the respective contact surface and across a major proportion of the diametrical width of the respective base or body.

3. An alarm device according to claim 1 or 2 wherein the elongate portion has an 30 enlarged head at an end thereof which is proximal to the periphery of the respective contact surface, and wherein the mouth of the elongate recess is enlarged relative to the remainder of the length of the elongate recess so as to receive the enlarged head of the elongate portion during a final stage of the lateral sliding engagement of the body with the base. 35

4. An alarm device according to any one of the preceding claims, wherein one or more retaining members are provided on either the base or the body to engage 10 with the mounting projection to retain the body in position with respect to the base.

5 5. An alarm device according to claim 4, wherein the one or more retaining members are clip members located within the mounting recess.

6. An alarm device according to any one of the preceding claims wherein the first contact surface is provided with one or more electrical terminals in electrical 10 connection with a remote power source.

7. An alarm device according to claim 6, wherein the second contact surface is provided with one or more electrical terminals which engage with the one or more electrical terminals of the first contact surface when the body is mounted to the 15 base to supply power to the operational components of the device from the remote power source.

8. An alarm device according to any one of claims I to 5, wherein the body includes a power source for powering the operational components of the device. 20

9. An alarm device according to claim 8, wherein the power source comprises one or more batteries.

10. An alarm device substantially as hereinbefore described with particular reference 25 to the accompanying Figures.