AU750941B2 - Vertical discharge exhaust canopy fan apparatus - Google Patents

Description

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AUSTRALIA

*Patents *Act 1990 Original Complete Specification Standard Patent P/00/011 Regulation 3.2 invention Title VERICA DICHAGEEXHAUST CANOPY FAN APPARATUS n-wntomeThe following statement is a full description of this invention, including the best method of promn

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1. I -1u exhaust cariopy fan This invention relatescve tn c3! diSChrge exAust canpy fan apparatus and involves an improvement in and/or modification of the invention disclosed and claimed in our standard patent 698736 granted 18th February, 1999 from application No 61973/96 lodged on 8th August, 1996.

The present specification incorporates the subject matter disclosed and claimed in patent No. 698736 by cross reference.

Apparatus of the main invention disclosed, claimed and illustrated in the specification of our patent 698736 is vertical-discharge exhaust canopy fan apparatus for upwardly discharging a stream of hot gases and fumes from 10 the canopy which has an outer housing and an inner housing, the outer housing forming a flue extension, the inner housing forms a cowling for an o electric motor of a motor/exhaust fan unit for forced exhausting of said hot exhaust gas stream from an opening at the top of the cowling; the bottom or lower part of the cowling interior being sealed against entry of hot exhaust gases and fumes exiting the flue and flowing into the flue extension and being :.:":directly connected to motor-cooling air flow entering external to the flue extension via one or more motor-cooling air inlet ducts entering through holes in an inclined base plate forming the bottom of the outer housing flue extension into ducts extending between the flue extension and the cowling, 2o cooling air external to the flue being drawn into the cowling via the ducts and onto the motor and through the cowling and being discharged through an opening at the top of the cowling by low pressure created by the flow of hot exhaust gases discharged through a gap in the top of the flue extension.

The improvement and/or modification of the main invention of patent 698736 comprises provision of a seal between flue and flue extension joint and provision of an upstanding rainwater run-off barrier and seal between the hot air exhaust flue and the outer housing flue extension against rainwater ingress into the flue, adding a rainwater downpipe to the inclined base plate -2of the outer housinQ flue extension via ho!e fo-rmed the base plate ouiside the rain water run-off barrier and via a collar arrangement.

More specifically an upstanding rainwater run-off barrier and seal is provided at the junction between the top of the hot air exhaust flue and a S lowest point of the inclined base plate forming the bottom of the outer housing flue extension against rainwater ingress.

Subsidiary modifications and/or improvements are streamlining by smooth curving of the contours of the fan cowling and also the outer housing or °ie flue extension of the original version of the canopy in patent 698736.

0 The main invention of our patent No. 698736 also included a .O.lei method of cooling a vertical discharge, exhaust canopy fan electric motor while operating within an inner housing forming a fan motor cowling mounted within an outer housing forming a hot exhaust gas flue, the method comprised introducing external cooling air inwardly and upwardly into the fan motor S cowling via ducts separate from and sealed off from the exhaust gas flue, the ".:":cooling air being passed over the motor and being sucked upwardly out of the top of the cowling above a central top opening of the cowling and through a peripheral gap below the cap atop the cowling by low pressure created by hot exhaust gas flow through an air jacket between the cowling and the flue. The 2o same method is used in the modification or improvement of the present application.

A non-limiting example of an embodiment or practical arrangement of the present modification and/or improvement of the main invention will now be described with reference to the accompanying drawing in which: Figure 1 is a diagrammatic, sectional vertical view of the modified vertical discharge exhaust canopy of the invention of the present application.

Referring to the drawing, the motor and fan assembly and linkage used in the modification is the same as that used and illustrated in the -3prci~fict1In an rne to, hi a en It case So does ut affparcn tie preseni modification and/or improvement and so has been omitted for clarity. However the outside cooling air ducts 19, 20 for cooling the fan motor and which extend between but which are sealed from the cowling and extension are also retained but have been included in the present specification and drawing for clarity. The gap at the junction between the top of the hot air exhaust flue and the inclined base plate 11 a forming the bottom or base plate of the outer housing of flue extension 11 of the embodiment of the main invention of the parent application has been sealed against rainwater ingress; the bottom of the Io outer housing or flue extension is now streamlined; the original baffle 15 of the parent invention has been removed and a baffle 125 now surrounds and is •sealed against the top of the hot air exhaust flue 10; a rainwater downpipe 26 has been added to extend below the inclined base plate 111 a of the flue extension or cowling outer housing 111 via a hole and collar arrangement and is also connected to a grease interceptor 27 (and water separator) in the form of a box with a removable lid 28 and incorporating a rainwater self-emptying Sowater siphon 29 both of which have been added to the bottom of the downpipe 26. The water level in the grease trap and water separator box is denoted by the letters WL and grease level is denoted by the letters GL water drains out automatically and the grease which floats on top can be manually periodically cleaned out for example annually. Rainwater is collected by means of the baffle 125 and flows down the downpipe 26 to exit the grease interceptor by automatic siphon action whenever the water level builds up in the grease interceptor water leaving the siphon flows into the usual storm water drain set up.

The shape of the cowling 112 and the outer housing 111 and base plate 11 la of the present modification has been made more streamlined than the cowling 12 and outer housing 11 and base 1 la of the parent application.

Claims (9)

1. In vertical-discharge exhaust canopy fan apparatus for upwardly discharging a stream of hot gases and fumes from the canopy which has an outer housing and an inner housing, the outer housing forming a flue extension, the inner housing forming a cowling for an electric motor of a motor/exhaust fan unit for forced exhausting of said hot exhaust gas stream from an opening at the top of the cowling; the bottom or lower part of the cowling interior being sealed against entry of hot exhaust gases and fumes exiting the flue and flowing into the flue extension and being directly connected to motor-cooling air flow entering external to the flue extension via one or more motor-cooling air inlet ducts entering through holes in an inclined base plate forming the bottom of the outer housing flue extension into ducts extending between the flue extension and the cowling, cooling air external to the flue being drawn into the cowling via the ducts and onto the motor and through the cowling and being discharged through an opening at the top of the cowling by low pressure created by the flow of hot exhaust gases discharged through a gap in the top of the flue extension, the improvement and/or modification comprising sealing a joint between flue and flue extension and providing an upstanding rainwater run-off barrier and seal between the hot air exhaust flue and the outer housing flue extension against rainwater ingress into the flue, adding a rainwater downpipe to the inclined base plate of the outer housing flue extension via a hole formed in the base plate outside the barrier and via a collar arrangement.

2. The improvement and/or modification according to claim 1 wherein the upstanding rainwater run-off barrier and seal is situated at the junction between the top of the hot air exhaust flue and a lowest point of the inclined base plate forming the bottom of the outer housing flue extension.

3. The improvement in or mndifi.tn of the apparatus according to claim 1 or claim 2 which includes a grease interceptor and water separator connected to the bottom of the down pipe.

4. The improvement in or modification of the apparatus according to any one of claims 1 to 3 wherein the grease interceptor and water separator is in the form of a box with a removable lid, water drains out of the box and the grease floats on top of the water and can be periodically cleaned out after removing the lid.

5. The improvement in or modification of the apparatus according to any one of claims 1 to 4 which includes a self-emptying water siphon in the lower part of the grease interceptor whereby rain water drains automatically therefrom.

6. The improvement and/or modification according to any .i preceding claim which additionally includes streamlining by smooth curving of the contours of the fan cowling of the original version of the canopy.

7. The improvement and/or modification according to any preceding claim which additionally includes streamlining by smooth curving of the contours of the outer housing or flue extension of the original version of the canopy.

8. The improvement in or modification of the apparatus according to any preceding claim which includes the outer housing or flue has a base or bottom around which there is an upstanding circumferential vertical exhaust-air deflecting and rain-deflecting fin or baffle.

9. Vertical discharge,exhaust canopy fan apparatus substantially as -to- hereinbefore dlis~hAmrge wItAh referenca 4- t4, 1copn~i U aing. Dated this 23 day of February, 1999 COMMERCIAL FOOD MACHINERY VIC. PTY.LTD. By Our Patent Attorney JOHN L.DAVIES CO 0:0.