GB2399930A

GB2399930A - Smoke alarm

Info

Publication number: GB2399930A
Application number: GB0405391A
Authority: GB
Inventors: Divjot Kapoor; Keely A Hibbit
Original assignee: Individual
Current assignee: Individual
Priority date: 2003-03-10
Filing date: 2004-03-10
Publication date: 2004-09-29
Anticipated expiration: 2024-03-10
Also published as: GB2399930B; GB0405391D0; GB0405316D0; GB0305473D0

Abstract

A smoke alarm device 11 comprises a housing 12 containing a smoke sensor 13, an audible warning device 14, a battery 15 and a circuit board 16. Interchangeable mounting plates 30 are provided for mounting the smoke alarm device in suitable locations in rooms. The housing has a back plate 20 which has a screw threaded recess 32. Each of the mounting plates has a screw threaded boss 31 which cooperated with the screw threaded recess 32 securing the selected mounting plate to the device. Each of the mounting plates has one or more means for temporarily locating the smoke alarm device in a suitable location in a room, the means for temporarily locating being different on different ones of the mounting plates. The different temporary locating means include a hook 40, a clamp, a bracket a string, a sucker a sprung hook and keyhole shaped holes.

Description

This invention relates to a personal smoke alarm device designed to be

mounted and dismounted temporarily in a variety of locations.

Conventional smoke alarm devices are designed to be permanently affixed to ceilings and walls of properties. Since smoke rises, smoke alarms should be positioned either on the ceiling or near the ceiling to enable them to be effective and pick up smoke rapidly. Typically, a smoke alarm device is mounted to a ceiling or wall as follows. Two screws are screwed into the ceiling or wall with the screw head and a small amount of the screw shank protruding. The base of the smoke alarm device contains two keyhole shaped holes into which the screws already fixed on the ceiling or wall are received. The smoke alarm device is placed over the screws so that the screw heads are received through the larger part of the holes. The whole smoke alarm device is then twisted so that the screw shanks are positioned in the smaller parts of the keyhole shaped holes, the screw heads overlapping the sides of the adjacent parts of the hole, thereby holding the smoke alarm device securely to the ceiling or wall.

The known device, by virtue of its size and weight, is easy to carry around, but it is not intended to be to be attached and detached repeatedly in different locations and may not be safe or functional upon a range of surfaces.

According to the present invention, there is provided a smoke alarm device comprising a smoke sensor, a housing for the smoke sensor, and interchangeable mounting plates for mounting the smoke alarm device in suitable locations in rooms, the housing including a back plate, the back plate and each of the mounting plates having interengageable fixing means for securing the housing selectively to any one of the mounting plates, each of the mounting plates having one or more means for temporarily locating the smoke alarm device in a suitable location in a room, the means for temporarily locating being different on different ones of the mounting plates.

In a preferred embodiment the smoke alarm device consists of a casing made of suitable material such as plastics, a circuit board, a sensor, an alarm and a 9V or similar battery. The sensor, alarm circuit and circuit board can be of known conventional design for a smoke alarm device.

The smoke alarm housing may be circular, square, rectangular or other shape.

The smoke alarm device may be completely sealed within the housing, in the sense that the housing cannot be opened to replace the battery. Openings are provided to allow the sensor to communicate with the ambient atmosphere. The device therefore has a designated operational Ike. The life of the unit will be calculated to ensure that the battery will remain charged and functioning during that life. The unit will then need to be discarded. An indication of the Ike of the smoke alarm device may be marked, for example by indelible printing or engraving on the housing of the smoke alarm. Although in this embodiment, it is intended that the device should be discarded after its specified life and consumers will be instructed to discard it after its expiry date, the alarm device may include a low battery warning device, for example a sound emitting device which emits an audible intermittent beeping sound should the battery begin to run down, to alert the consumer that the battery is not sufficiently charged and the unit is not functioning to its full capability. This is to prevent a consumer inadvertently using the device when the battery is not functioning and therefore the device is not working.

In another embodiment of the invention, the smoke alarm device is not sealed and the battery within the device can be replaced when necessary.

The smoke alarm device is designed to be attached and detached to a suitable location with ease using one of the series of mounting plates. Such a device would be particularly useful and important, for example, in countries where fire protection laws are flouted or where fire protection and safety equipment is not compulsory.

The specific purpose of the present invention is to provide a portable smoke detecting device that is easily mounted and dismounted for use in a variety of different locations, including, without limitation, hotels, hostels and camping motor vehicles. In the preferred embodiment, each mounting plate contains one or more means for temporarily locating the device in a suitable location which may comprise one or more fixing mechanisms for attaching the smoke alarm unit temporarily to a variety of surfaces or a stand for placing the device on a surface.

In particular, because of the wide range of mounting plates (and therefore fixing mechanisms) which can be used with the device, the consumer can easily ensure that the smoke alarm device is placed in a location sufficiently high from the floor for it to function correctly.

In the preferred embodiment the smoke alarm device has a central screw threaded circular recess in the back plate corresponding to where the a conventional smoke alarm device would ordinarily be attached to a wall or ceiling The central screw threaded boss preferably has a diameter of approximately 25mm (1 inch). The base of the smoke alarm unit does not have the standard fixing holes of a conventional smoke alarm device, which is designed to be fixed permanently to a ceiling or wall. The back plate of the device may be flat apart from the aforesaid recess. A series of mounting plates, which may be the same shape and size as the smoke alarm device, may be provided, each having a boss of equal heighVdepth, size and shape, to the circular recess in the smoke alarm back plate. The boss on each mounting plate has a screw thread around the circumference corresponding to the threading around the circumference of the recess in the smoke alarm device back plate. When placed together and twisted, the screw thread on the boss mates with the screw thread on the recess allowing the back plate of the housing to be securely fixed to the mounting plate. The mounting plates contain different fixing mechanisms, which allow the smoke alarm device, when securely fastened to the mounting plate, to be fixed to a variety of different surfaces.

In an alternative embodiment, the back plate of the smoke alarm unit could be provided with the boss and the mounting plates of the device could contain the recess. Again there would be a corresponding screw thread around the circumference of both the boss and the recess, and when placed together and twisted, the threading on the boss would engage with the threading on the recess allowing both to be securely attached to one another.

The interengaging fixing means for securing the housing to the mounting may take other forms. For example they may comprise dovetail shaped key and keyway, a hook and burr fastener, or a clip and clip engagement portion.

Embodiments of the invention will now be described by way of example with reference to the accompanying drawings in which: Fig 1 shows a cross section through a smoke alarm device in accordance with the invention with a mounting plate with a hook; Fig 2 shows exploded and assembled perspective views of the smoke alarm device device of Fig 1; Fig 3 shows exploded and assembled perspective views, similar to Fig 2, of the smoke alarm device device of Fig 1 fitted with an alternative mounting plate with a clamping device; Fig 4 shows exploded and assembled perspective views, similar to Fig 2, of the smoke alarm device device of Fig 1 fitted with an alternative mounting plate with plate with a string; Fig 5 shows exploded and assembled perspective views, similar to Fig 2, of the smoke alarm device device of Fig 1 fitted with an alternative mounting plate; with a sucker; Fig 6 shows exploded and assembled perspective views, similar to Fig 2, of the smoke alarm device device of Fig 1 fitted with an alternative mounting plate with a free-standing bracket; Fig 7 shows exploded and assembled perspective views, similar to Fig 2, of the smoke alarm device device of Fig 1 fitted with an alternative mounting plate with a sprung hook; and Fig 8 shows exploded and assembled perspective views, similar to Fig 2, of the smoke alarm device device of Fig 1 fitted with an alternative mounting plate with nail/screw engaging holes.

The smoke alarm unit, recess and boss (with the recess on the base of the smoke alarm unit and the boss on the back plate) along with a series of examples of the back plates are shown in detail on the attached diagrams.

Referring to Fig 1, this shows a smoke alarm device 11 comprising a circular housing 12 of moulded plastics material containing a smoke sensor 13, an audible warning device 14, a battery 15 and a circuit board 16. The housing has a front wall 17 with vents 18 to allow the interior of the housing to communicate with the ambient atmosphere surrounding the device, and a reset button 19 for reseeing the alarm once it has gone off. All the components described so far can be of conventional construction.

The housing has a back plate 20 on which smoke alarm device components are mounted and which is secured to the rear of the peripheral wall 21 of the housing by adhesive or welding so that the components are sealed within the housing in the sense that the battery cannot be replaced. On the front of the housing is indelibly printed the expiry date for the device (not shown).

In an alternative embodiment, the back plate 20 is detachably mounted to the peripheral wall 21 of the housing by having a peripheral screw thread which mates with a screw thread on the inside of the peripheral wall. In this embodiment the battery can be replaced when it is run down.

The smoke alarm device 11 has a series of interchangeable mounting plates for mounting the smoke alarm device in suitable locations in rooms. One such mounting plate 30 is shown in Fig 1.

The back plate 20 and each of the mounting plates have interengageable fixing means for securing the housing selectively to any one of the mounting plates. In the embodiment of Fig 1, the interengageable fixing means comprise a screw threaded boss 31 and a complementary screw threaded recess 32. The screw threaded recess 32 is formed in the rear side of the back plate 20. There is a cooperating screw threaded boss 31 on the front of each of the series of mounting plates 30. The boss is screwed into the recess to fix the housing of the alarm device 11 securely to the mounting plate 30.

Each of the mounting plates has one or more means for temporarily locating the smoke alarm device in a suitable location in a room. The means for temporarily locating the device is different on different mounting plates. In the embodiment of Fig 1 the locating means is in the form of a hook 40 which is permanently attached to the mounting plate 30. The hook 40 allows the device to be hooked onto a variety of surfaces or room fixtures. By way of example, the hook 40 would allow the device to hooked on to picture or curtain rails or picture frames and thereby become functional.

Fig 3 shows the device of Fig 1 with an another mounting plate 30a. The plate 30a has a screw clamp or vice 50 permanently attached to the back of the mounting plate. The front of the mounting plate is identical to that of the mounting plate 30 of Fig 1. It has a screw threaded boss which mates with the threading in the recess of the back plate of the smoke alarm housing. When the screw 51 of the clamp 50 is turned the gap between the jaws if the clamp will narrow or widen to grip or release anything placed between them such as a protruding surface.

The clamp or vice 50 allows the device to be clamped onto a variety of surfaces fixtures. By way of example, this would allow the device to be clamped onto shelves, picture rails, curtain rails, light fittings, or picture, window or door frames in a room and thereby become functional.

Fig 4 shows the device of Fig 1 with another mounting plate sob. The plate 30b has string, flex or tape 55 attached to a hole in the rear surface of the mounting plate. The string, flex or tape will thread through a hole in the back plate allowing the device to be hung or tied to a variety of objects. By way of example, this would allow the device to be tied to light fitting or curtain rails and thereby become functional.

Fig 5 shows the device of Fig 1 with another mounting plate 30c. The plate 30c has a rubber sucker 60 attached to its rear surface with the cup shaped part facing rearwardly. The sucker 60 allows the device to be attached to a variety of surfaces. By way of example, this would allow the device to be attached to glossy surfaces such as doors, walls, tiles, mirrors or glass and thereby become functional. The mounting plate of Fig 5 may be modified by having more than one sucker attached to it.

Fig 6 shows the device of Fig 1 with another mounting plate 30d. The plate 30d has a bracket 70 attached to it. The bracket comprises an upstanding mounting portion 71 which is secured to the back of the mounting plate 70 and a horizontal surface engaging portion 72 projecting rearwardly from the mounting portion at an angle to its lower edge so that when the mounting plate is secured to the back of the housing, the device can be placed on a variety of surfaces. By way of example, this would allow the device to be positioned on shelves or on top of wardrobes and thereby become functional. The bracket may have a hinged portion connecting it to the mounting plate Bed. This would allow the bracket to be retracted when not in use.

Fig 7 shows the device of Fig 1 with another mounting plate Bee. The plate 30e has a sprung hook 80 attached to the rear of the plate. The sprung hook comprises two parts, a straight mounting part 81 and a curved hook part 82 which are joined together by a spring hinge 83. The straight mounting part 81 is secured to the mounting plate Bee. The spring hinge 83 biases the hook part 82 towards the straight part 81. The spring hook allows the device to be attached to a variety of surfaces and fixtures. By way of example, the sprung hook would allow the device to be hooked over a picture frame or television bracket and thereby become functional.

Fig 8 shows the device of Fig 1 with another mounting plate 30f. The plate 30f has a series of keyhole shaped holes 90 of differing sizes for fitting over the heads of nails, screws or similar projections. When fitted to the housing, the plate 30f allows the device to be attached to a variety of surfaces. By way of example, this would allow the device to be hooked onto a screw, nail or hook protruding from a wall and thereby become functional.

Mounting plates with other means for securing the device temporarily in a suitable location may be provided in accordance with the invention, and one mounting plate may have more than one such means. For example, a combination of two or more of the hook, clamp, string, sucker, sprung hook and nail/screw holes features of Figs 2, 3, 4, 5, 6 7 and 8. Therefore, with one smoke alarm device and a few such multipurpose mounting plates, it would be possible for the alarm device to function in almost any residency, irrespective of the interior.

As previously mentioned, the position of the boss and recess can be reversed.

The back plates can also be designed to be affixed/fastened to the smoke alarm base by various other means, including but not limited to, clip, pop, slide, click, fasten, attach, connect, join, unite or other fastening mechanism.

Claims

1. A smoke alarm device comprising a smoke sensor, a housing for the smoke sensor, and interchangeable mounting plates for mounting the smoke alarm device in suitable locations in rooms, the housing including a back plate, the back plate and each of the mounting plates having interengageable fixing means for securing the housing selectively to any one of the mounting plates, each of the mounting plates having one or more means for temporarily locating the smoke alarm device in a suitable location in a room, the means for temporarily locating being different on different ones of the mounting plates.

2. A smoke alarm device according to claim 1 in which the interengageable fixing means comprise a screw threaded boss and a complementary screw threaded recess.

3. A smoke alarm device according to claim 2 in which the screw threaded recess is in the back plate and there is a cooperating screw threaded boss on each of the mounting plates.

4. A smoke alarm device according to any of the preceding claims in which there are more than one different means for temporarily locating on at least one of the mounting plates.

5. A smoke alarm device according to any of the preceding claims in which the housing includes a battery and means for indicating when the battery has expired, the battery being sealed within the housing so that it cannot be replaced.

6. A smoke alarm device according to claim 5 in which the means for indicating when the battery has expired is an audible alarm.

7. A smoke alarm device according to any of the preceding claims in which the means for temporarily locating include a hook.

8. A smoke alarm device according to any of the preceding claims in which the means for temporarily locating include a clamp.

9. A smoke alarm device according to any of the preceding claims in which the means for temporarily locating include a string or tape tie.

10. A smoke alarm device according to any of the preceding claims in which the means for temporarily locating include a sucker.

11. A smoke alarm device according to any of the preceding claims in which the means for temporarily locating include a free standing 1 5 bracket.

12. A smoke alarm device according to any of the preceding claims in which the means for temporarily locating include a spring loaded hook.

13. A smoke alarm device according to any of the preceding claims in which the means for temporarily locating include a keyhole shaped slot.

14. A smoke alarm device substantially as hereinbefore described with reference to the accompanying drawings.

Fig Title Key No. Fig. 2 Travel Smoke Alarm The main smoke alarm unit without the rear - Hook attachment in place.

The back plate for the smoke alarm comes with a variety of securing options which can be easily screwed to the base unit with a twist of the wrist.

Fig. 3 Travel Smoke Alarm The main smoke alarm unit without the rear Clamping Option attachment in place.

Once the smoke alarm base unit is attached, the hook is operational and can be used to fix the alarm to a variety of surfaces.

Once the smoke alarm base unit is attached, the clamp is operational and can be used to fix the alarm to a variety of surfaces.

F \1.ets20t)4Mun\47268_Bubs Ka,ooor table I doe doe Fig Title Key No. Fig. 4 Travel Smoke Alarm The main smoke alarm unit with the rear attachment String in place.

Once the smoke alarm base unit is attached, the string can be used to tie the alarm to different objects.

Fig. 5 Travel Smoke Alarm The main smoke alarm unit without the rear Sucker attachment in place.

Once the smoke alarm base unit is attached, the sucker' can be used to 'stick' the unit in the desired position.

F \Lets2004 Jttn\4726X Bubs Kapoot table I doc doc Fig. 6 Travel Smoke Alarm The main smoke alarm unit without the rear - Free-Standing attachment in place.

Bracket The back plate for the smoke alarm comes with a variety of securing options which can be easily screwed to the base unit with a twist of the wrist.

This attachment allows for the unit to be placed on any flat surface whilst enabling it to be operational.

Fig. 7 Travel Smoke Alarm The main smoke alarm unit without the rear Sprung Hook attachment in place.

Fig. 8 Travel Smoke Alarm The main smoke alarm unit without the rear Nail/Screw Hook attachment in place.

This attachment allows for the unit to be 'hooked' on to a protruding nail or screw (Back view).

Once the smoke alarm base unit is attached, the hook' can be used to hang the unit in the desired position.

F \Lets2004\Ju\4726h Blabs Kapoor table I doc doc