GB2354623A

GB2354623A - Smoke extractor system

Info

Publication number: GB2354623A
Application number: GB9922617A
Authority: GB
Inventors: Kishore Manilal Thakrar
Original assignee: Innovative Products NZ Ltd
Current assignee: Innovative Products NZ Ltd
Priority date: 1999-09-25
Filing date: 1999-09-25
Publication date: 2001-03-28
Also published as: GB9922617D0

Abstract

A smoke extractor system includes a switch 6, a smoke detection and processing unit 1 and an air purification unit 7. The switch has the following settings - Off, Sensor and Override. When Sensor setting is selected, power is supplied to the smoke detection and processing unit, which in turn enables power to the air purification unit during the period smoke density measured lies between two pre-determined levels, in order to remove the smoke. The switch may be set to Override setting to supply power to the air purification unit but not the smoke detection and processing unit.

Description

2354623 SMOKE EXTRACTOR SYSTEM This invention reiates to a smoke extractor

system.

In many places, cigarette and cigar smoke is present at levels where it becomes a nuisance to others. The nuisance may take the form of eye discomfort, the smell in the air or the smell infusing into clothing. In addition it forces passive smoking to others present.

Currently an extractor fan is used on many occasions, supplemented at times by an air purifier. However in many cases these are switched on only after an excessive amount of smoke has already built-up, and it can then take a substantial time for the smoke level to be reduced to an acceptable ievel.

According to the present invention there is provided a smoke extractor system comprising a switch, a smoke detection and processing unit and an air purification unit such that the switch supplies power to the smoke detection and processing unit which in turn supplies power to the air purification unit during the period smoke density measured lies between two pre-determined levels.

Specific Embodiments of the invention will now be described by way of example with reference to the accompanying drawings in which:- Figure I shows circuit diagram of a smoke extractor system.

Figure 2 shows in perspective, a smoke extractor system.

Figure 3 shows a top view of the smoke detection and processing unit.

Referring to the drawings, the smoke extractor system comprises a switch 6, an air purification und 7, and a smoke detection and processing unit I consisting of a smoke detection sensor 2, and a smoke sensitivity adjuster 3. The system may optionally have an LED 8 that flashes when the smoke sensor requires replacement owing to 2 contamination. The switch has the following settings - Off, Sensor and Override. When Sensor setting is selected on the switch, power is supplied to the smoke detection and processing unit via power cable 4. The smoke detection and processing unit enables power to the air purification unit via power cable 5 during the period smoke density measured lies between two pre-determined levels, the minimum level and the maximum level. When Override setting is selected, the air purification unit operates independently of any smoke detection.

The optional LED 8 flashes when the smoke sensor contamination degrades the system operation significantly, and is an indication that the smoke sensor requires replacement. The smoke sensor contamination may be measured using a variety of techniques. One technique is to monitor electrical measurements within the smoke chamber, and if over a long period this measurement reading is consistent with that of a significantly contaminated sensor, then this is taken to indicate significant sensor contamination. Another technique is to have a twin chamber system, comprising a smoke chamber and a sealed chamber. The electrical measurements in the smoke chamber is compared with the sealed chamber, and a large discrepancy over a period of time is taken to indicate significant sensor contamination.

In order to use the smoke extractor system, the smoke detection and processing unit I is installed on a ceiling or a wall, the switch 6 is connected into a mains or other power supply outlet, the power cable 4 run to and connected to the smoke detection and processing unit, and the power cable 6 run to and connected to an air purification unit 7. If the air purification unit is an extractor fan, it is normally installed to an external wall, or if it is an air purifier, the unit is normally mounted onto the ceiling. The smoke sensitivity may be adjusted using the smoke sensitivity adjuster 3 and the switch set to Sensor setting. To facilitate operation of the air purification unit independently of smoke detection, the switch is set to Override setting. The smoke detection and processing unit may be designed to make the smoke detection sensor 2 easily replaceable/renewable. The smoke detection sensor should be replaced regularly, or when the sensor contaminated LED 8 flashes in those systems with the option present.

Claims

3 CLAIMS

I A smoke extractor system comprising a switch, a smoke detection and processing unit and an air purification unit such that the switch supplies power to the smoke detection and processing unit which in turn supplies power to the air purification unit during the period smoke density measured lies between two pre-determined leve Is.
2 A smoke extractor system as claimed in Claim 1, in which the air purification unit is an extractor fan.
3 A smoke extractor system as claimed 'in Claim 1 or 2 wherein the smoke detection and processing unit has a smoke sensitivity adjuster.
4 A smoke extractor system as claimed in Claim 1, 2 or 3 wherein the smoke detection sensor is easily replaceable/renewable.
A smoke extractor system as claimed in any one of Claims 1 to 4 wherein the smoke detection and processing unit has circuitry such that power to the air purification unit continues to be supplied for a fixed duration once the smoke density measured falls below the lower pre-determined level.
6 A smoke extractor system as claimed in any one of Claims 1 to 5 wherein the switch has a setting to supply power to the air purification unit, irrespective of smoke detection.
7 A smoke extractor system as claimed in any one of Claims 1 to 6 wherein the smoke detection and processing unit has circuitry such that a fixed duration after the smoke density measured continually exceeds the higher pre-determined level, power to the air purification unit is disabled.
8 A smoke extractor system as claimed in any one of Claims 1 to 7 wherein the system may include an LED that flashes when the circuitry in the smoke detection and processing unit determines that the smoke sensor has become unacceptably contaminated.
9 A smoke extractor system substantially as hereinbefore described with reference to any one of the accompanying drawings.