US20170082298A1

US20170082298A1 - Extractor hood for professional ovens for cooking food

Info

Publication number: US20170082298A1
Application number: US14/857,394
Authority: US
Inventors: Italo Tommasin
Original assignee: PIRON Srl
Current assignee: PIRON Srl
Priority date: 2015-09-17
Filing date: 2015-09-17
Publication date: 2017-03-23

Abstract

The present invention relates to a extractor hood for professional ovens for cooking food, of the type comprising a box-like containment body for a motorized fan adapted to aspirate by means of a front inlet, and one or more rear inlets, said rear inlet being shaped to convey hot and humid exhaust gases to a labyrinth with cold walls which is interposed between said rear inlets and said fan, said extractor hood being characterized in that said cold walls have an internal containment cavity for cooling water, and at the upper edge of each outer cooling surface multiple side-by-side holes or through openings, or a single longitudinal opening for the outflow of said cooling water are defined, provided below the cool walls are means for collecting and diverting said water and the condensation that has formed towards a discharge duct.

Description

The present invention relates to an extractor hood for professional ovens for cooking food.

BACKGROUND OF THE INVENTION

The professional forced air recirculation ovens for cooking food known today, generally comprise, in the rear part of the muffle and connected thereto, a chamber for air ventilation and heating.
Said ovens are provided with means for introducing water in the heating chamber, to be nebulized by the associated ventilation and heating means, thus blowing water vapor on the food in the cooking chamber.
The humidity in the muffle is determined by a first step of the mechanical breaking of water drops, nebulizing the same, by the action of the rotating fans of one or more ventilators, and by a second water vaporization step mechanically nebulized by the action of heating elements surrounding the fans.
The hot and humid air is then evacuated from the muffle generally in a natural way, i.e. not forced, by means of vent stacks formed by simple tubes putting the cooking chamber in direct communication with the outside.
In this way the hot exhaust gases, having temperatures ranging from 100° C. to 180° C., are dispersed in the environment.
Extractor hoods are advantageously associated to said ovens having a front inlet, for the suction of the exhaust gases exiting the oven from the opening of the access door to the cooking chamber, and suction ducts for the hot and humid exhaust gases exiting from the vent stacks of the oven.
The hot and humid exhaust gases exiting the vent stacks of the professional oven are generally taken in by the fan of the hood and are forced to travel a labyrinth of cold walls, touching the latter, in order to obtain the condensation of the steam contained in the exhaust gases.
The cold walls touched by hot exhaust gases are made by one or more tanks filled with water at a predetermined temperature.
Said cooling system for the hot and humid exhaust gases exiting from the vent stacks of a professional oven for cooking food, although widespread and appreciated, has some drawbacks.
A first drawback is caused by the heating of the cooling and condensation water contained in the tank-walls touched by hot and humid exhaust gases.
Accordingly, when the tank-walls undergo an excessive increase in temperature, their capacity to cool the hot exhaust gases and to condense the steam of said hot and humid exhaust gases diminishes, causing the overall overheating of the extractor hood and the releasing towards the outside of hot exhaust gases and steam having a high environmental impact.
In said situation the tank-walls must be drained and refilled with water at proper temperature.
Furthermore, the condensation which is deposited on the tank-walls tends to remain on the walls themselves decreasing the heat exchange capacity thereof, descending from the outer surface of the tank-walls themselves only by the action of the weight force.

SUMMARY OF THE INVENTION

The object of the present invention is to provide an extractor hood for professional ovens for cooking food suited to obviate the mentioned limits of the known art.
Within this object, a purpose of the invention is to provide an extractor hood capable of high and constant efficiency over time.
Another purpose of the invention is to provide an extractor hood whose heat exchange walls, for hot and humid exhaust gases exiting from the vent stacks of an associated oven, are easy to clean and free from condensation.
This object, as well as these and other purposes which will become apparent hereinafter, are achieved by an extractor hood for professional ovens for cooking food, of the type comprising a box-like containment body for a motorized ventilator adapted to aspirate by means of a front inlet, for the suction of the exhaust gases exiting the oven from an access door to the cooking chamber, and one or more rear inlets for the hot and humid exhaust gases exiting from the vent stacks, said rear inlets being shaped for conveying said hot and humid exhaust gases to a labyrinth for cooling and dehumidification with cold walls, interposed between said inlets and said rear fan, said extractor hood is characterized in that said cold walls have an internal cavity for containing cooling water, and defined at the upper edge of each outer cooling surface are multiple side-by-side holes or through openings, or a single longitudinal opening, for the outflow of said cooling water, wherein below said cold walls there are means for collecting and diverting said water and condensation that has formed towards a discharge duct.

BRIEF DESCRIPTION OF THE DRAWINGS

Further characteristics and advantages of the invention will become apparent from the description of a preferred, but not exclusive, embodiment of the extractor hood according to the invention, illustrated, by way of non-limitative example in the accompanying drawings, wherein:

FIG. 1 illustrates a perspective view from below of an extractor hood according to the invention;

FIG. 2 represents a top perspective view, with no cover, of the extractor hood according to the invention;

FIG. 3 represents a second diagrammatic side view in section of a extractor hood according to the invention;

FIG. 4 is a detail of FIG. 3.

DETAILED DESCRIPTION OF THE INVENTION

With reference to the cited figures, an extractor hood 10 for professional ovens for cooking food, is indicated as a whole by number 10.
Said extractor hood 10 is of the type comprising a box-like containment body 11 for a motorized fan 12, clearly visible in FIG. 2, adapted to aspirate through a front inlet 13, and one or more rear inlets, in the present embodiment two rear inlets 14 or 15.
The rear inlets 14 or 15, better described below, are shaped to convey hot and humid exhaust gases to a labyrinth for cooling and dehumidification 16 with cool walls 17 and 18, interposed between said rear inlet 14 and 15 and the fan 12.
The peculiarity of the extractor hood 10 according to the invention lies in the fact that the cold walls 17 and 18 have an internal containment cavity, respectively 19 and 20, for cooling water, and at the upper edge of each outer cooling surface 21, 22, 23, 24 multiple side-by- side holes 25 and 26, or alternatively through openings of non-circular profile, or a single longitudinal opening, such as a slot, for the outflow of said cooling water are defined.
Provided below the cold walls 17 and 18 are means, described below, for collecting and diverting the cooling water and the condensation towards a discharge duct 27.
The rear inlets 14 and 15 are constituted by two sleeves for connection to a corresponding number of rising pipes for the hot and humid exhaust gases exiting from the corresponding vent stacks of a professional oven.
Said sleeves direct the exhaust gases directly into the cooling and dehumidification labyrinth 16.
The cooling and dehumidification labyrinth 16 is constituted by a box-like container 28 inside which a winding path is defined, being formed by six substantially equidistant side by side walls, 29, 30, 17, 31, 18 and 32, that are arranged alternately so as to allow the passage of the exhaust gases above or below a wall.
Two of the central walls are the cold walls 17 and 18, as clearly shown in FIG. 4.
Each of said cold walls 17 and 18 consists of an enclosure made of bent sheet metal, provided with a water inlet hole 33 and 34 respectively to which a delivery pipe 35 and 36 is interconnected.
The delivery pipes 35 and 36 receive the cooling water from an electric valve 37 with a pipe and a two-way union 38.
The electric valve 37 is controlled by a temperature sensor 39, shown in FIG. 2, which measures the temperature inside the cold walls 17 and 18.
The means for collecting and diverting the cooling water and the condensation that has formed towards a discharge duct 27 are constituted, in the present non-limiting embodiment of the invention, by the inclined bottom 40 of the box-like container 28 of the labyrinth 16, which diverts the water descending along the outer surfaces of the walls, as well as the precipitated condensation, towards the discharge duct 27.
The invention resides in the fact that the cold walls 17 and 18 are cooled from the outside by a system of holes 25 and 26 of small diameter arranged in a suited manner so as to create a film of cold water along all the outer surfaces of the cold walls themselves.
The water flowing out from the holes 25 and 26 and the condensation are discharged outside.
The outflow of water from the holes is made possible by the action of the electric valve 37 controlled by the temperature sensor 39: if the temperature rises above a preset value, the water flows into the tank-cavities of the cold walls 17 and 18 and flows out from the holes.
It is found in use that the invention achieves the object and the intended purposes.
In particular, with the invention an extraction hood capable of high and constant efficiency over time has been developed, thanks to the action of the water flowing out from the holes of the cold walls, that by touching the outer surfaces of the same keeps the latter at the correct temperature and clears the condensation.
Said heat exchange walls, for hot and humid exhaust gases exiting from the vent stacks of an associated oven, are then easily clean and free of condensation thanks to the presence of the holes allowing the water to fall and to the means for delivering water to the cold chambers whose internal cavities are in fact tanks for said cooling and dehumidification water.
The invention, thus conceived, is susceptible of numerous modifications or variations, all falling within the inventive concept; moreover, all the details may be replaced with other technically equivalent elements.
Practically, the material used, as long as it is compatible with the specific use, as well as the size or the actual shape, may be any according to the requirements and the background art.
Where the features and techniques mentioned in any claim are followed by reference marks, said marks have been assigned with the sole purpose of increasing the intelligibility of the claims and accordingly said reference marks do not have any limiting effect on the interpretation of each element identified by way of example by said reference marks.

Claims

1. An extractor hood (10) for professional ovens for cooking food, of the type comprising a box-like containment body (11) for a motorized fan (12) adapted to aspirate through a front inlet (13), and one or more rear inlets (14, 15), said rear inlets (14, 15) being shaped to convey hot and humid exhaust gases to a labyrinth for cooling and dehumidification (16) with cold walls (17, 18), which is interposed between said rear inlets (14, 15) and said fan (12), said extractor hood being characterized in that said cold walls (17, 18) have an internal containment cavity (19, 20) for cooling water, and at the upper edge of each outer cooling surface (21, 22, 23, 24) there being multiple side-by-side holes (25, 26) or through openings, or a single longitudinal opening, for the outflow of said cooling water, below said cold walls there being means for collecting and diverting said water and the condensation that has formed toward a discharge duct (27).

2. The extractor hood according to claim 1, characterized in that said rear inlets (14, 15) are constituted by a corresponding number of sleeves for connection to a corresponding number of rising pipes for the hot and humid exhaust gases that exit from corresponding vent stacks, for example of a professional oven, said sleeves conveying the exhaust gases directly into the cooling and dehumidification labyrinths (16).

3. The extractor hood according to claim 1, characterized in that said cooling and dehumidification labyrinth (16) is constituted by a box-like container (28) inside which there is a winding path formed by a series of substantially equidistant side-by-side walls (29, 30, 17, 31, 18, 32) that are arranged alternately so as to allow the passage of the exhaust gases above or below a wall, at least one of the central walls being one of said cold walls (17, 18), as clearly visible in FIG. 4.

4. The extractor hood according to the preceding claim, characterized in that each one of said cold walls (17, 18) comprises an enclosure made of bent sheet metal, provided with a water inlet hole (33, 34) at which a delivery pipe (35, 36) is interconnected.

5. The extractor hood according to the preceding claim, characterized in that said delivery pipes (35, 36) receive the cooling water from an electric valve (37) with a pipe and a two-way union (38).

6. The extractor hood according to the preceding claim, characterized in that the electric valve (37) is controlled by a temperature sensor (39), visible in FIG. 2, which measures the temperature inside the cold walls (17, 18).

7. The extractor hood according to claim 1, characterized in that said means for collecting and diverting the cooling water and the condensation that has formed toward a discharge duct (27) comprise an inclined bottom (40) of the box-like container (28) of the labyrinth (16), which diverts the water that descends by sliding along the outer surfaces of the walls, as well as the precipitated condensation, toward the discharge duct (27).