GB1591451A - Extractor vents - Google Patents

Description

(54) IMPROVEMENTS IN OR RELATING TO EXTRACTOR VENTS (71) We, KEMRON PROPERTIES PITY.

LTD., an Ausfralian Body Corporate, of 320 St Kilda Road, Melbourne, in the State of Victoria, Australia, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention relates to extractor vents, and range-hoods and work-benches having extractor vents.

According to one aspect of the present invention there is provided an extractor vent comprising a hollow housing having on one side thereof inlet ports extending around substantially the entire periphery of the side to create a zone of low pressure around the periphery of said side leaving the centre portion of the side at a higher pressure, an outlet from the housing spaced from said side, and a fan located within the housing to draw air through the housing via the inlet ports and the outlet.

According to another aspect of the present invention there is provided a rangehood comprising an extractor vent according to the invention wherein said centre portion of the side comprises a dense filter screen to allow air flow therethrough at a lower velocity than that through said inlet ports.

According to a further aspect of the present invention there is provided a workbench having an extractor vent according to the invention wherein said centre portion of the side provides a work-top of the bench.

Specific embodiments of the invention will now be described by way of example, reference being made to the accompanying drawings in which: Figure 1 illustrates a work bench according to the invention; Figure 2 illustrates an extractor vent according to the invention formed as a range-hood and; Figure 3 illustrates a range-hood according to the invention.

An embodiment of the present invention is illustrated in Figure 1 and comprises the provision of a work-top 5 which is bounded on all sides by peripheral inlet ports 6, 7, 8 and 9 which are flush with the level of the work-top. A down draught into these inlet ports about the periphery of the worktop, ensures that any fumes are unlikely to circulate out of the work area. A con trol panel 10 enables the fan speed to be adjusted as well as providing ancillary power outlets.

The work-bench installation is useful where there are no overhead cupboards within'which to install a rangehood or where ducting is difficult to arrange from a rangehood positioned above a working surface. In one aspect not illustrated where working surfaces on bench tops require exhausting, a work-bench according to the present invention can be used which includes additional filters and allows recycling of the air directly into the roof and thus avoids the need for ducting out of the room.

Figures 2 and 3 show schematic cross sections of a rangehood 12 with peripheral vents 13. As can be seen in Figure 2 where the rangehood adequately covers the stove surface all fumes, steam, etc. rising from pots and pans on the stove top will be enclosed within a peripheral updraught of air which is drawn into the peripheral vents 13. As can be seen from the drawings, inclined vanes are provided in the inlet ports to direct air towards the centre of the rangehood.

In Figure 2 the central area 14 is impervious sheet metal but in Figure 3 the central portion 15 is a dense filter material which enables gaseous fluid flow through the central region but at a lower velocity and volume rate than in the peripheral region of the rangehood's under surface.

The peripheral exhaust region can be defined by a filter screen of a desired shape and the central region can either be an impervious sheet or a filter screen of dense material. This latter arrangement provides a simple means of providing an exhaust draught over the whole surface but a higher velocity draught, i.e. lower pressure, in the peripheral region. Alternatively separate ducts can be used for the central portion of the under surface and for the peripheral region. In each of these arrangements, a single exhaust fan can be used to provide the principal exhaust draught in the peripheral region and a minor draught in the central region. It would be possible to use two or more fans to draw air through the peripheral and central areas of the under surface but generally a single conventional exhaust fan located above the under surface is sufficient to create the necessary draught.

As mentioned above the central area of the under surface of the rangehood may be air permeable and may be a filter more dense in structure than the peripheral filter.

Some airflow through the central area is preferred to avoid condensation of steam and fats in this area. By providing a degree of air permeability and airflow through this area condensation is reduced.

The ranghood may, apart from its under surface, be of conventional construction.

An internal arrangement of baffles to encourage fast airflow from the periphery of the under surface in preference to the central region may be incorporated into the rangehood housing. The exhaust ducting from the housing is conventional and may be from the top or rear of the housing depending on where the rangehood is to be installed. The exhaust fan is located within the housing. As in conventional systems the exhaust airstream may be recycled to the room from where it was extracted or may be exhausted into the atmosphere. When recycling is adopted additional filters are incorporated into the hood to ensure that the recycled air has retained none of the contaminants contained in the updraught from the cooling area.

The central area of the under surface may conveniently incorporate a light fitting especially where a well lit cooking range or work surface is required. The placing of the inlet ports around the periphery is particularly useful in areas requiring efficient exhausing of cooking contaminants with maximum lighting.

WHAT WE CLAIM IS:- 1. An extractor vent comprising a hollow housing having on one side thereof inlet ports extending around substantially the entire periphery of the side to create a zone of low pressure around the periphery of said side leaving the centre portion of the side at a higher pressure, an outlet from the housing spaced from said side and a fan located within the housing to draw air through the housing via the inlet ports and the outlet.

2. An extractor vent as claimed in claim 1 wherein vanes are provided in the inlet ports, the vanes being inclined to direct air entering the housing towards the centre of the housing.

3. A range-hood comprising an extractor vent as claimed in any preceding claim wherein said centre portion of the side comprises a dense filter screen to allow air flow therethrough at lower velocity than that through said inlet ports.

4. A work-bench having an extractor vent as claimed in claim 1 or 2 wherein said centre portion of the side provides a worktop of the bench.

5. An extractor vent substantially as hereinbefore described with reference to and ilustrated in the acompanying drawings.

6. A range-hood substantially as hereinbefore described with reference to and as illustrated in Figure 2 or 3 of the accompanying drawings.

7. A work-bench substantially as hereinbefore described with reference to and as illustrated in Figure 1 of the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (7)

**WARNING** start of CLMS field may overlap end of DESC **. peripheral region. Alternatively separate ducts can be used for the central portion of the under surface and for the peripheral region. In each of these arrangements, a single exhaust fan can be used to provide the principal exhaust draught in the peripheral region and a minor draught in the central region. It would be possible to use two or more fans to draw air through the peripheral and central areas of the under surface but generally a single conventional exhaust fan located above the under surface is sufficient to create the necessary draught. As mentioned above the central area of the under surface of the rangehood may be air permeable and may be a filter more dense in structure than the peripheral filter. Some airflow through the central area is preferred to avoid condensation of steam and fats in this area. By providing a degree of air permeability and airflow through this area condensation is reduced. The ranghood may, apart from its under surface, be of conventional construction. An internal arrangement of baffles to encourage fast airflow from the periphery of the under surface in preference to the central region may be incorporated into the rangehood housing. The exhaust ducting from the housing is conventional and may be from the top or rear of the housing depending on where the rangehood is to be installed. The exhaust fan is located within the housing. As in conventional systems the exhaust airstream may be recycled to the room from where it was extracted or may be exhausted into the atmosphere. When recycling is adopted additional filters are incorporated into the hood to ensure that the recycled air has retained none of the contaminants contained in the updraught from the cooling area. The central area of the under surface may conveniently incorporate a light fitting especially where a well lit cooking range or work surface is required. The placing of the inlet ports around the periphery is particularly useful in areas requiring efficient exhausing of cooking contaminants with maximum lighting. WHAT WE CLAIM IS:-

1. An extractor vent comprising a hollow housing having on one side thereof inlet ports extending around substantially the entire periphery of the side to create a zone of low pressure around the periphery of said side leaving the centre portion of the side at a higher pressure, an outlet from the housing spaced from said side and a fan located within the housing to draw air through the housing via the inlet ports and the outlet.

2. An extractor vent as claimed in claim 1 wherein vanes are provided in the inlet ports, the vanes being inclined to direct air entering the housing towards the centre of the housing.

3. A range-hood comprising an extractor vent as claimed in any preceding claim wherein said centre portion of the side comprises a dense filter screen to allow air flow therethrough at lower velocity than that through said inlet ports.

4. A work-bench having an extractor vent as claimed in claim 1 or 2 wherein said centre portion of the side provides a worktop of the bench.

5. An extractor vent substantially as hereinbefore described with reference to and ilustrated in the acompanying drawings.

6. A range-hood substantially as hereinbefore described with reference to and as illustrated in Figure 2 or 3 of the accompanying drawings.

7. A work-bench substantially as hereinbefore described with reference to and as illustrated in Figure 1 of the accompanying drawings.