GB2459323A

GB2459323A - Networked alarm devices with address set by plug device

Info

Publication number: GB2459323A
Application number: GB0806413A
Authority: GB
Inventors: Manhar Amlani
Original assignee: RED DOT TECHNOLOGIES Ltd
Current assignee: RED DOT TECHNOLOGIES Ltd
Priority date: 2008-04-09
Filing date: 2008-04-09
Publication date: 2009-10-28
Anticipated expiration: 2028-04-09
Also published as: GB2459323B; GB0806413D0

Abstract

An alarm transducer 10, such as a fire detector / sounder devices 10 or call points 14, is addressable over a network 11,12 and may comprise a detector head 16 attached to a base 15. Each transducer has an electrical terminal 30 provided with a plurality of contacts TO - T5 (fig 5) the terminal receiving one of a number of coding plug devices 17 (also figs 2,3). The coding plug device 17 comprises a unique arrangement of electrically interconnected pins PO - P5 which thus interconnect contacts TO - T5 of terminal 30. The pin arrangement (figs 2) preferably comprises a common pin connected to one or more coding pins, to produce a 5-bit binary code which sets the address simply by inserting the coding plug 17. The coding plug 17 has a label portion 20 having a mark showing the address (se moulding 21 fig 2) when the transducer is installed. The coding plugs may be provided as a set, preferably as a frangibly interconnected moulding (figs 2,3).

Description

ADDRESSABLE ALARM TRANSDUCER

This invention relates to an addressable alarm transducer.

Alarm systems are known which comprise plurality of transducers such as heat/smoke detectors, sounders, manual call points and other input/output devices connected across one or more pairs of wires which extend from a control panel. In use, the control panel is able to sense an alarm condition if one of the detectors or call points is activated. The control panel then activates the sounders.

In large buildings, it is desirable for the control panel to indicate the source of the activation and in this regard, it is known to provide each fire alarm detector with a unique address code, which can be recognised by the control panel. Also, another advantage of addressable transducers is that the control panel can send control commands to a particular transducer.

EP0191239 discloses an addressable alarm system in which each of the detectors has a unique address code, so that the control panel can address one or more of the detectors and so that the control panel can recognise which detector has been activated. Typically, each detector comprises a plurality of switches which are set to give it a unique binary address code. A disadvantage of this arrangement is that it is complicated for alarm engineers to understand and set these binary codes.

EP0362985 attempts to overcome this problem and discloses a detector comprising a base for fitting to a ceiling or other surface and a removable sensor or so-called head. A key card is provided for insertion into the base, the card having a. plurality of frangible formations, the presence or absence of which define a binary code which can be read by corresponding switches on the head when the latter is fitted to the base. In use, an engineer has to configure each key card to form a unique binary code by removing appropriate formations therefrom.

A disadvantage of this arrangement is that the engineer can make a mistake and can incorrectly code a card or perform a duplicate card. Another disadvantage is that the provision of switches on the head is costly and the switches can be liable to failure.

We have now devised an alarm transducer which alleviates the above-mentioned problem.

In accordance with the present invention, as seen from a first aspect, there is provided an alarm transducer comprising an alarm transducer device having an electrical terminal provided with a plurality of contacts and a coding device for connecting to the terminal, the coding device being arranged to form a unique configuration of electrical connections between the contacts of the terminal.

In use, a plurality of coding devices are provided, each being arranged to form a unique configuration of electrical connections between the contacts of the terminal.

Thus, an engineer merely has to connect one of the coding devices to a terminal of the transducer, in order to set the address code of the transducer. The transducer may comprise a heat detector, a smoke detector, a gas detector, a sounder, a manual call point or an input/output device for controlling an external device such as a door closer.

Preferably the coding device is provided with a region which provides an alpha-numeric indication of the address code.

Preferably the region projects from a housing of the transducer device, so that it can be viewed when the transducer is mounted in-situ. Preferably the region is detachable so that the coding device can be used on occasions when it is not desirable to have a visible an alpha-numeric indication of the address code when the transducer is mounted in-situ.

Preferably the terminal comprises a socket for receiving a complimentary plug of the coding device.

Preferably the socket comprises an array of conductive apertures on a printed circuit board of the transducer device. This arrangement avoids the need to provide a physical terminal component on the transducer device.

Preferably the coding device comprises pins which engage into selected apertures on the printed circuit board Preferably the pins are formed of a conductive plastics material or of a plastics material which is coated with a conductive material, so that the devices can be formed by injection moulding. Alternatively, the pins may be formed of metal.

Also in accordance with the present invention, as seen from the first aspect, there is provided a kit of parts comprising an alarm transducer device having an electrical terminal provided with a plurality of contacts and a plurality of coding devices for selectively connecting to the terminal, each coding device being arranged from a unique configuration of electrical connections between the contacts of the transducer terminal.

Preferably the coding devices are arranged to form different binary inputs to an electronic component connected to the terminal of the transducer device.

The coding device may for example have a common contact for connecting to a corresponding contact of the transducer terminal which carries a fixed voltage representing a binary 0 or 1. The coding device then connects that contact of the terminal to select other contacts of the terminal. Typically there may be five other contacts so that a unique binary code of between 0 and 2 (i.e. 32) can be produced.

Also in accordance with the present invention, as seen from a second aspect, there is provided a coding assembly for alarm transducer devices, the assembly comprising a plurality of coding devices each having a terminal for mating with a corresponding terminal of a respective alarm transducer device, wherein each coding device is arranged to form a unique configuration of electrical connections between the contacts of the transducer terminal.

In use, an engineer merely has to select one of the ready-made coding devices from the set and fit it to an alarm transducer in order to code the latter. This process is extremely straight forward and the risk of making mistakes is alleviated. Preferably said coding devices are frangibly interconnected to each other in a set.

Preferably at least a portion of the coding devices are formed of a moulded material, the devices preferably being frangibly interconnected by the moulding.

Preferably the coding devices are connected to a supporting runner of the moulding each coding device being frangibly connected to the runner. The runner may form a frame around the coding devices.

Preferably each coding device is provided with a region which provides an alpha-numeric indication of the address code, said alpha-numeric indication preferably being provided by the moulding.

Preferably the coding devices are at least partially formed of a moulded plastics material. The devices or the terminals of the devices may be formed of a conductive plastics material or of a plastics material which is coated with a conductive material.

Preferably the terminals of the coding devices each comprise a unique pattern of pins or other contacts, the presence of absence of which define the configuration of electrical connection between the contacts of the transducer terminal and hence the address code.

Preferably each pin or contact terminal of a coding device is electrically connected to each other pin or contact of the terminal.

An embodiment of the present invention will now be described by way of an example only and with reference to the accompanying drawings, which: Figure 1 is a block diagram of an addressable alarm system in accordance with the present invention; Figure 2 is a perspective view from above of an assembly of coding devices of the alarm system of Figure 1; Figure 3 is a perspective view from below of the assembly of coding devices of Figure 2; Figure 4 is a perspective bottom view of a portion of heat/smoke detector of the alarm system of Figure 1; and Figure 5 is a schematic diagram of a portion of an electronic circuit of the detector of Figure 4.

Referring to Figure 1 of the drawings, there is shown an addressable alarm system comprising a control panel 13 and a plurality of combined detector and sounder devices 10 connected in parallel across a pair of wires 11, 12 extending from the control panel 13. A plurality of other transducers, such as manual call points 14 may also be connected in parallel across the wires 11, 12.

Each device 10 comprises a base 15 for fitting to a ceiling or other surface and a removable sensing head 16. The base 15 comprises terminals for connecting to the wires 11, 12 and contacts for connecting the terminals with corresponding contacts on the head 16 when the latter is fitted to the base 15. As will be explained hereinafter, each device 10 and each call point 14 comprises a circuit for receiving a unique coding device 17, in order to allocate a unique 5-bit address code thereto.

Referring to Figures 2 and 3 of the drawings, the coding devices 17 are supplied already coded and as a set, with the devices 17 of each set being interconnected.

The number of devices 17 in each set may vary but typically there may be 32 devices in total, supplied as 2 sets of 16 devices. Each device 17 comprises a rectangular body portion 18 carrying a conductive terminal 19, which is provided with one or more pins P (i.e. P0 -P5 as shown for device 31 in Figure 2).

A flat tab 20 extends outwardly from the body 18, the distal end of the tab 20 comprising an enlarged region 21 which carries a numeric decimal representation (eg 1 -32) of that the address code provided by that device 17. The proximal end of the tab 20 is connected to the body 18 via a frangible web 23. A further numeric decimal representation of the address code provided by the device is preferably formed on the underside of the body 18. The devices 17 are formed of a moulded plastics material, with each device of the set being frangibly interconnected by an elongate moulding runner 22.

The terminals 19 of the devices 17 may be formed as conductive inserts for engaging with the body 18, for example the inserts may be formed from a conductive plastics material or metal. Alternatively, the terminals 19 may be coated with a conductive material. Each terminal 19 comprises a common pin P0 and a unique pattern of five other pins P1 -P5, thereby enabling each device to define a unique 5-bid binary code in accordance with the following table: 2 2 2 22 21

PIN PIN PIN PIN PIN

VALUE p P4 P3 P2 P1 1 0 0 0 0 1 2 0 0 0 1 0 3 0 0 0 1 1 4 0 0 1 0 0 0 0 1 0 1 6 0 0 1 1 0 7 0 0 1 1 1 8 0 1 0 0 0 9 0 1 0 0 1 0 1 0 1 0 11 0 1 0 1 1 12 0 1 1 0 0 13 0 1 1 0 1 14 0 1 1 1 0 0 1 1 1 1 16 1 0 0 0 0 17 1 0 0 0 1 18 1 0 0 1 0 19 1 0 0 1 1 1 0 1 0 0 21 1 0 1 0 1 22 1 0 1 1 0 23 1 0 1 1 1 24 1 1 0 0 0 1 1 0 0 1 26 1 1 0 1 0 27 1 1 0 1 1 28 1 1 1 0 0 29 1 1 1 0 1 1 1 1 1 0 31 1 1 1 1 1 32 0 0 0 0 0 Referring to Figure 4 of the drawings, in use a selected coding device 17 is detached from its adjacent device by breaking the runner 22. The selected coding device 17 is then inserted into a socket 24 formed in the bottom wall of the head 16 of the detector, such that the terminal 19 thereof makes contact with a complementary terminal inside the detector 10. The tab 20 of the coding device projects outwardly of the detector 10, such that the decimal number on the distal end thereof can be viewed from below when the detector is installed in-situ.

Referring to Figure 5 of the drawings, there is shown a portion of the electronic circuit inside the detector head 16. The circuit comprises an array of plated apertures formed on a printed circuit board, the apertures defining a terminal 30 for receiving the pins P of a coding device 17. The terminal 30 comprises a first aperture TO which is connected to the positive voltage rail 31 and is arranged to receive the common pin P0 of the coding device 17. The remaining five apertures of the terminal are arranged to respectively receive the other pins P1 -P5 of the coding device 17. Each of these five apertures are connected to respective input terminals of a processing device 32. Each input is normally of the processing device 32 is connected to the negative rail 33 via a respective resistor e.g. 34.

When a coding device 17 is connected to the terminal 30, the device 17 selectively applies the positive voltage to the input of the processor 32 when a pin P1 -P5 is present on its terminal 19. When no pin is present, a negative voltage is applied to the processor 32 by virtue of the resistors 34. In this manner, each device 17 can produce a unique binary address code for the detector 10. The coding devices 17 can also be fitted to other addressable devices connected to the control panel 13 of the alarm system.

It will be appreciated that the coding devices 17 are simple and inexpensive to manufacture, yet easily enable an address code to be set without the risk of making mistakes or forming duplicate address codes.

Claims

CLAIMS1. An alarm transducer comprising an alarm transducer device having an electrical terminal provided with a plurality of contacts and a coding device for connecting to the terminal, the coding device being arranged to form a unique configuration of electrical connections between the contacts of the terminal.
2. An alarm transducer as claimed in claim 1, in which the coding device is provided with a region which provides an alpha-numeric indication of the address code.
3. An alarm transducer as claimed in claim 2, in which the region projects from a housing of the transducer device, so that it can be viewed when the transducer is mounted in-situ.
4. An alarm transducer as claimed in claim 3, in which the region is detachable.
5. An alarm transducer as claimed in any preceding claim, in which the terminal comprises a socket for receiving a complimentary plug of the coding device.
6. An alarm transducer as claimed in claim 5, in which the socket comprises an array of conductive apertures on a printed circuit board of the transducer device.
7. An alarm transducer as claimed in claim 6, in which the coding device comprises pins which engage into selected apertures on the printed circuit board.
8. An alarm transducer as claimed in claim 7, in which the pins are formed of a conductive plastics material.
9. An alarm transducer as claimed in claim 7, in which the pins are formed of a plastics material which is coated with a conductive material.
10. An alarm transducer as claimed in claim 7, in which the pins are formed of metal.
11. An alarm transducer substantially as herein described with reference to the accompanying drawings.
12. A kit of parts comprising an alarm transducer device having an electrical terminal provided with a plurality of contacts and a plurality of coding devices for selectively connecting to the terminal, each coding device being arranged from a unique configuration of electrical connections between the contacts of the transducer terminal.
13. A kit of parts as claimed in claim 12, in which the coding devices are arranged to form different binary inputs to an electronic component connected to the terminal of the transducer device.
14. A kit of parts as claimed in claims 12 or claim 13, in which each coding device has a commonly-positioned contact for connecting to a corresponding contact of the transducer terminal which carries a fixed voltage representing a binary Oorl.
15. A kit of parts as claimed in claim 14, in which each coding device connects said fixed voltage terminal to a unique configuration of other terminals of the transducer.
16. A kit of parts substantially as herein described with reference to the accompanying drawings.
17. A coding assembly for alarm transducer devices, the assembly comprising a plurality of coding devices each having a terminal for mating with a corresponding terminal of a respective alarm transducer device, wherein each coding device is arranged to form a unique configuration of electrical connections between the contacts of the transducer terminal.
18. A coding assembly as claimed in claim 17, in which said coding devices are frangibly interconnected to each other in a set.
19. A coding assembly as claimed in claim 18, in which at least a portion of the coding devices comprise a moulding formed of a moulded material.
20. A coding assembly as claimed in claim 19, in which the devices are frangibly interconnected by the moulding.
21. A coding assembly as claimed in claim 20, in which the coding devices are connected to a supporting runner of the moulding, each coding device being frangibly connected to the runner.
22. A coding assembly as claimed in claim 21, in which the runner may forms a frame around the coding devices.
23. A coding assembly as claimed in any of claims 17 to 22, in which each coding device is provided with a region which provides an alpha-numeric indication of the address code.
24. A coding assembly as claimed in claim 23 as appended to claim 19, in which, said alpha-numeric indication is provided by the moulding.
25. A coding assembly as claimed in claim 19, in which the coding devices are at least partially formed of a moulded plastics material.
26. A coding assembly as claimed in claim 25, in which the terminals of the devices are formed of a conductive plastics material.
27. A coding assembly as claimed in claim 25, in which the terminals of the devices are formed of a plastics material which is coated with a conductive material.
28.A coding assembly as claimed in any of claims 17 to 27, in which the terminals of the coding devices each comprise a unique pattern of pins or other contacts, the presence of absence of which define the configuration of electrical connection between the contacts of the transducer terminal and hence the address code.
29. A coding assembly substantially as herein described with reference to the accompanying drawings.