EP3546834A1

EP3546834A1 - Oven provided with a washing system

Info

Publication number: EP3546834A1
Application number: EP19165686.7A
Authority: EP
Inventors: Luca Gemelli; Fabio Segato
Original assignee: Angelo Po Grandi Cucine SpA
Current assignee: Angelo Po Grandi Cucine SpA
Priority date: 2018-03-29
Filing date: 2019-03-28
Publication date: 2019-10-02
Also published as: IT201800004080A1

Abstract

An oven (1) for cooking food provided with a washing system that comprises a supplying and distributing assembly comprising a supply chamber (6) that is suppliable with a washing liquid in a washing procedure for washing a cooking chamber (3) of the oven (1) and with water in a rinsing procedure for rinsing said cooking chamber (3), said supplying assembly further comprising a distributor element (9, 10) that communicates with the supply chamber (6) and is configured for distributing said washing liquid, or said water, both in a cooking zone (3a) of the cooking chamber (3) and in a heating zone (3b) of the cooking chamber (3).

Description

The invention relates to an oven for cooking food provided with a washing system.
Washing systems are known for washing an oven for cooking food that comprise:

a collecting and storage tank placed below the cooking chamber that collects a washing liquid that deposits on the bottom of the cooking chamber during washing of the latter; on the bottom of the cooking chamber an opening is provided that communicates with the collecting tank;
a plumbing circuit connected to a water supply network, which enables water to be delivered inside the collecting tank;
a recirculating pump that removes the washing liquid collected in the collecting tank and sends it to a distribution circuit, which receives the washing liquid from the pump and, through one or more pipes, reintroduces and distributes the washing liquid in the cooking chamber;
a closing and/or emptying system for the collecting tank that can comprise, for example, discharge valve or pump. This system, arranged between the collecting tank and the oven drain, enables the tank to be emptied when required, by pouring the contents thereof through the drain of the oven.

The washing processes used in the ovens that use a washing system as disclosed above, can be of various type, but all comprise at least one dirt-removal procedure, consisting of the following steps:

filling the collecting tank with water through the plumbing circuit; in this step, the closing/emptying system of the collecting tank has to be arranged so as to prevent the water exiting from the collecting tank to the drain of the oven;
inserting into the washing system a detergent chemical product; said inserting can be manual (the operator inserts the product inside the cooking chamber, in the collecting tank or in another point of the plumbing circuit) or automatic by a system dedicated to this purpose (for example dosing pumps that remove the correct quantity of product from an external tank and load it into the circuit);
recirculating the washing liquid (consisting of the mixture of water and detergent) through the recirculating pump and the distribution system;
emptying the collecting tank at the end of the washing procedure, through the closing/emptying system that pours the contents of the tank down the drain of the oven.

After the washing procedure one or more rinsing steps are always provided that comprise:

filling the collecting tank with water through the plumbing circuit;
recirculating the water through the recirculating pump and the distribution system in the cooking chamber;
emptying the tank through the discharge valve or through the discharge pump.

In the washing procedure, the step of recirculating the washing fluid is the most important step and the efficacy of the washing depends thereupon. During this step in fact, the washing fluid consisting of water and of a detergent product is dispensed continuously inside the cooking chamber and has to be distributed as evenly as possible over all the surfaces of the cooking chamber, so as to remove the dirt as effectively as possible and in as short a time as possible. The distribution system and, in particular, the manner in which the washing fluid is dispensed and distributed inside the cooking chamber is accordingly of fundamental importance for obtaining an optimum washing result with minimal consumption of energy, water and detergent chemical product.
The recirculating step is important also in the rinsing procedure where the rinsing fluid consists of only water. Optimum distribution of the flow of water inside the cooking chamber helps to rinse better the walls of the cooking chamber and remove more effectively and faster the residues of the detergent chemical product.
Cooking chambers of ovens are generally divided into two zones by a wall known as a "conveyor", which separates the cooking zone in which the trays or the grilles are arranged, on which the foods to be cooked are arranged, from a heating zone in which hot air is produced that is sent to the cooking zone. Inside the heating zone a heating element (electrical resistance or gas heat exchanger) and a fan are arranged for circulating the air. The conveyor has a circular opening in the centre at the suction port of the fan and has openings, generally arranged along the perimeter thereof or near thereto, through which hot air, heated by the heating element, passes from the heating zone to the cooking zone. In some types of oven, at the conveyor a pipe or a duct is located that leads a flow of water coming from the outside to the suction zone of the fan. This flow of water is used to generate steam: the water exiting the duct is, in fact, nebulized by the fan or by another device connected thereto and radially diverted outside by the movement of the fan and, subsequently, knocking the heating elements, or passing near the heating elements, is transformed into steam.
It is important to obtain good washing efficacy in both zones of the cooking chamber, because possible residual dirt in the heating zone could be conveyed by the action of the fan into the cooking zone and onto the food being cooked. Whatever the constructional solution adopted for distributing and dispensing the washing fluid inside the cooking chamber, the motion of the air generated by the fan helps to redistribute the washing liquid between the two zones of the cooking chamber but, as will be disclosed below, this action is often not sufficient to ensure on its own an optimum result in both zones of the cooking chamber.
In some ovens, the distribution of the washing fluid in the cooking chamber occurs by exploiting only the action of the fan.
One typical structural solution of these ovens provides for dispensing washing fluid near the perimeter of the fan. In this manner the distribution of the fluid in the heating zone is certainly optimal, but it is not possible to obtain optimum distribution of the washing fluid in the cooking zone, in particular on the walls opposite the conveyor, where the fan struggles to convey the washing fluid in an acceptable quantity.
One example of this type of oven is disclosed in US patent application US2002/0036196 where the washing fluid is dispensed along a circular zone that is concentric around the fan with the flow directed in a direction opposite the flow of air exiting the fan itself.
In international patent application WO2013/088227 an oven is disclosed in which the washing fluid is dispensed into the heat exchanger zone through an opening on the top of the cooking chamber.
In other models of ovens, the washing fluid is dispensed from the top of the cooking chamber opposite, and near, the conveyor, so that the freely falling flow passes in front of the port of the fan and is sucked up by the fan. The sucking effect of the fan is not however sufficient to suck all the flow and accordingly part of the flow directly arrives on the bottom of the cooking chamber and from here to the drain, without contributing to wash the walls.
International patent application WO2007/098732 discloses an oven in which the washing fluid is dispensed on the top of the cooking chamber inside the cooking zone but near the conveyor and the suction zone of the fan.
The advantage of these structural solutions lies in the simplicity and moderate cost, because, normally, only one entry point of the washing liquid inside the cooking chamber is provided and no particular washing liquid dispensing systems are necessary. The main drawback of these systems is that the washing efficacy of the cooking zone is totally delegated to the action of the fan.
In further models of ovens, washing fluid is dispensed directly into the cooking zone (usually through the top of the cooking chamber). In this case however the flow of air into the cooking zone is usually too weak to divert the entering flow of washing liquid and act in such a way that it hits the vertical walls of the cooking chamber. Accordingly, in these types of ovens, the distribution circuit is provided with one or more dispensing devices that have the task of diverting the entering flow of washing liquid to the walls of the cooking chamber. The dispensing devices can be fixed (for example distributing heads provided with nozzles, sprinklers, etc) or movable (for example comprising a rotating arm).
German utility model DE202012104832U1 and US patent application US2003/0159721 describe two different structural solutions for the dispensing system, arranged in both the solutions on the top of the cooking chamber approximately in the centre of the cooking zone.
Also the international patent application WO2015/091803 discloses a particular dispensing device arranged on the top of the cooking chamber in the cooking zone. In this case the dispensing device is also used to distribute the detergent chemical product.
A further different structural solution for the dispensing system is disclosed in US patent application US2008/0223357 , but where the dispensing system is positioned in the centre of the cooking zone or, alternatively, near the conveyor.
The advantage of these structural solutions is better washing efficacy for washing the cooking zone. Nevertheless, the washing efficacy of the heating zone is limited, because only a minimal portion of the washing fluid reaches this zone. Further, these systems are more expensive than those disclosed previously because of the washing liquid dispensing and distribution devices. Lastly, a further drawback is that the dispensing devices provided with nozzles may be subject to clogging because of solid dirt particles that may be present in the washing fluid.
It is possible to combine the two previously cited solutions, i.e. the delivery of the washing liquid into the heating zone and the delivery of the washing liquid in the cooking zone, using two entry points of the washing fluid: a first entry point in the heating zone near the fan and a second entry point in the cooking zone, still using a spraying system on the latter. In this manner, the washing efficacy of both the cooking zone and the heating zone is optimum. Of course, the drawback of this solution is the high cost.
In European patent application EP0801271A1 , different solutions are presented, where the washing fluid is dispensed inside the port of the fan, both in the same direction as and in the opposite direction to the flow of air sucked by the fan or, in another structural solution, the washing fluid is dispensed on the top of the cooking chamber at the cooking zone through a particular dispensing device. These two alternative structural versions can be used simultaneously.
Another embodiment of this type is illustrated in German patent application DE 10 2012 004197 in which different solutions for dispensing the washing fluid are disclosed, some arranged in the cooking zone and others at the suction zone of the fan.
Lastly, it should be noted that in ovens in which steam production for cooking food is provided, the system for supplying water to produce steam is totally independent of the system for supplying water to wash the cooking chamber, which makes the structure of the oven more complex and expensive.
One object of the present invention is to provide an oven for cooking food provided with a washing system that is simple and cheap to make and enables all the zones of the cooking chamber to be reached with an appropriate flow of washing liquid.
A further object of the present invention is to provide a washing system for washing an oven that can be at least partially integrated with the system for supplying water for producing steam during cooking of the food.
The objects of the present invention are reached with an oven for cooking food provided with a washing system according to claim 1.
Owing to the invention, it is possible to make simply and cheaply a washing system for washing an oven for cooking food that enables a flow of washing liquid to be sent inside the oven that ensures that each part of the cooking zone and of the heating zone of the cooking chamber is reached by a suitable quantity of washing liquid. Further, a part of the washing system according to the invention can be used to supply water for producing steam during cooking of the food.
Further features and advantages of the invention are clear from the following description and from the enclosed drawings that illustrate a non-limiting embodiment of a washing system for washing an oven according to the present invention.

Figure 1 shows a section of an oven for cooking food with the washing liquid supply system according to the invention;
Figure 2 shows an enlarged detail of Figure 1;
Figure 3 illustrates a first distributing element for distributing the washing liquid and the rinsing liquid;
Figure 4 illustrates a second distributing element for distributing the washing liquid and the rinsing liquid;
Figure 5 illustrates a third distributing element for distributing the washing liquid and the rinsing liquid;
Figure 6 illustrates the assembly of the distributing elements for distributing the washing liquid and the rinsing liquid.

Figure 1 shows a section of an oven 1 for cooking food according to the invention, provided with a body 2, inside which a cooking chamber 3 is defined, divided into a cooking zone 3a, inside which cooking of the food occurs, and into a heating zone 3b in which air is heated that is sent to the cooking zone 3a.
In the cooking zone 3a, support elements 4 can be provided, which extend in a direction that is perpendicular to the plane of Figure 1, on which trays or grilles (not shown) can be placed that are intended to support the food during cooking.
Inside the heating zone 3, there are arranged a fan 11, driven by a motor (not visible in the figures) and a heating element 16, consisting, for example, of a plurality of electrical resistances or of a heat exchanger, which heats the air in the heating zone 3b.
The cooking zone 3a and the heating zone 3b are separated by a wall 15, commonly known as a "conveyor", in which a first opening (not visible in the figures) is made at the suction zone 5 of the fan 11 and one or more second openings (which are not visible in the figures) at the delivery zone of the fan 11. Through the first opening, the fan 11 sucks air from the cooking zone 3, whereas through the second opening, or the second openings, the fan 11 sends to the cooking zone 3a heated air removed from the heating zone 3b. In the suction zone 5 of the fan 11, a nebulizing element 20 is arranged that is configured for nebulizing a liquid sent to said suction zone 5. One embodiment of the nebulizing element 20 is disclosed in Italian patent for industrial invention n. 0001368785, in the name of the same applicant, to which the reader is referred for structural details of the nebulizing element 20.
The supply system according to the invention comprises a supplying and distributing assembly of a washing liquid configured for supplying and distributing said washing liquid in the cooking zone 3a and in the heating zone 3b. The supplying and distributing assembly comprises a supply chamber 6, arranged, for example, in the upper part of the heating zone 3b, near an upper wall 17 of the oven 1. The supply chamber 6 can be supplied with a washing liquid, consisting of a mixture of water and of a detergent substance, by a first supply conduit 7 and with water by a second supply conduit 8. The supply chamber 6 communicates, through a first opening 13, with a distributor element, configured for distributing said washing liquid both in the cooking zone 3a and in the heating zone 3b. The distributor element comprises a tubular conduit 9, a first end 18 of which communicates with said first opening 13 and a second end 19 of which, opposite the first end 18, terminates with a chute 10 oriented towards a suction zone 5 of the fan 11. The supply chamber 6 is provided with a bottom 21 tilted by an angle α with respect to a longitudinal axis A of the tubular conduit 9. The tilt angle α of the bottom 21 with respect to the longitudinal axis A has a size comprised advantageously between 30° and 60°. In one preferred embodiment of the present invention, the bottom 21 is tilted by about 45° with respect to said longitudinal axis A.
In said first end 18 of the tubular conduit 9 a second opening 14, facing the first opening 13 and communicating with the cooking chamber 3, is obtained.
The second opening 14 is staggered downwards with respect to the first opening 13 in a direction parallel to the longitudinal axis A of the tubular conduit 9. Preferably, the second opening 14 is so arranged that a lower edge 22 thereof is located on an extension of the bottom 21 of the supply chamber 6, i.e. on a plane containing the bottom 21, or slightly higher than said plane, at a distance not above 20 mm. In order to perform the washing procedure of the cooking chamber 3, into the supply chamber 6, through the first supply conduit 7, a washing fluid is delivered consisting of a mixture of water and of a detergent chemical substance. The flow rate of the washing fluid is comprised between about 10 1/min and about 20 1/min at a supply pressure comprised between 0.3 bar and 0.8 bar. In one preferred embodiment of the present invention, the flow rate of said mixture is 15 1/min, with a supply pressure of about 0.6 bar.
The flow of washing fluid delivered into the supply chamber 6 is directed from the bottom 21 to the first opening 13 and the second opening 14.
As a result of the tilt of the bottom 21 and the arrangement of the second opening 14, the flow of washing liquid knocks against the lower edge 22 of the second opening 14 and divides into two separate flows: a first flow passes through the second opening 14 and reaches directly into the cooking zone 3a, whereas a second flow remains inside the tubular conduit 9, reaches the second end 19 of the tubular conduit 9 and is directed from the chute 10 into a suction zone 5 of the fan 11. It should be noted that, by varying the position of the lower edge 22 of the opening 14 with respect to the plane containing the bottom 21, it is possible to vary the relative proportions between said first flow and said second flow.
The second flow, upon reaching the suction zone 5 of the fan 11, in which the nebulizing element 20 is arranged, is nebulized and distributed over the entire heating zone 3b, thus washing said zone. The first flow, after passing through the second opening 14, is distributed over all parts of the cooking zone 3a, owing to the kinetic energy thereof.
In order to improve further the distribution of the washing liquid in the cooking zone 3a it is possible to provide flow-distributor elements that are arranged inside the cooking zone 3a near said second opening 14 and interact with said first flow.
Some embodiments of a distributing flow element will be disclosed below, with reference to Figures 3 to 6.
At the end of washing of the cooking chamber 3, a rinsing procedure is conducted by delivering water into the supply chamber 6, again by the first supply conduit 7, at a flow rate comprised between about 10 l/min and about 20 l/min at a supply pressure comprised between 0.3 bar and 0.8 bar, so as to obtain complete rinsing of the cooking zone 3a and the heating zone 3b. In a preferred embodiment of the present invention, the flow rate of rinsing water is 15 1/min, at a supply pressure of about 0.6 bar.
When steam has to be generated for cooking the food, a flow of water is delivered into the supply chamber 6 by the second supply conduit 8. The flow rate of water delivered into the supply chamber 6 for producing of steam is much lower than the flow rate of washing liquid, or of rinsing water, delivered into the supply chamber 6 during the washing and rinsing procedures. Advantageously, the flow rate of water delivered into the supply chamber 6 for producing steam is comprised between about 0.10 1/min and about 0.35 1/min. In one preferred embodiment of the present invention, the flow rate of water for producing of steam is equal to about 0.15 1/min.
Owing to the very low flow rate and, thus, the very low speed, the water for producing of steam delivered into the supply chamber 6 does not reach the second opening 14 of the tubular conduit 9 and flows by gravity until it reaches the chute 10, which directs the water into the suction zone of the fan 11 on the nebulizing element 20, which nebulizes the water and sends it to the heating element, or against the heating element, so that the water is transformed into steam, which is then delivered to the cooking zone 3a. In Figure 3, a first flow distributor element 23 is illustrated by means of which the washing liquid is distributed inside the cooking zone 3a of the cooking chamber 3, so as to obtain a distribution of the washing liquid as uniform as possible that enables all the parts of the cooking zone 3a to be reached, so as to obtain an effective washing of the entire cooking zone 3a.
The first flow distributor element 23 has a parallelepiped-shaped body 24, with a cage-shaped structure 25 that extends on three adjacent sides of the body 24 and is open at a fourth side.
The body 24 is provided with a first pair of hooking elements 26 and with a second pair of hooking elements 27, by means of which the flow distributor element 23 can be hooked onto the tubular conduit 9, at the second opening 14, so that the latter is at the open fourth side of the cage-shaped structure 25.
When the first flow of washing liquid passes through the second opening 14, it enters the first flow distributor element 23 through the fourth open side of the cage-shaped structure 25 and interacts with said structure that divides said first flow of washing liquid into a plurality of parts that are distributed substantially evenly inside the cooking zone 3a, ensuring complete washing of the latter.
Similarly, during the rinsing step, the flow of rinsing liquid that passes through the second opening 14 enters the first flow distributor element 23 and, by interacting with the cage structure 25, is divided and distributed substantially evenly in the cooking zone 3a, ensuring effective rinsing of the latter.
In Figure 4, a second flow distributor element 28 is illustrated that comprises a parallelepipedon-shaped body 29 consisting of a lower part 29a and an upper part 29b connected together by two uprights 29c. Between the two uprights 29c, a passage 30 is defined through which the first flow of washing, or rinsing, liquid can pass. The body 29 is provided with a flow distributor device 31 that comprises a first chute-shaped part 32 that widens towards the outside of the body 29, a second part 33 connected to an end 40 of the first part 32 facing the outside of the body 29, said second part 33 curving upwards, and a third part 34 connected to an end 41 of the second part 33 opposite said end 40 of the first part 32. The third part 34 is tilted upwards. The second part 33 and the third part 34 are provided with holes 35.
The body 29, like the body 24 of the first flow distributor element 23, is provided with a first pair of hooking elements 26 and with a second pair of hooking elements 27, by means of which the second flow distributor element 28 can be hooked to the tubular conduit 9, at the second opening 14.
When the first flow of washing liquid traverses the second opening 14 and enters the second flow distributor element 28 through the passage 30, it is distributed on the first part 32 of the device 31 and is partially diverted upwards by the second part 33 and by the third part 34 of the flow distributor device 31 and partially downwards, passing through the holes 35, so as to be distributed substantially evenly inside the cooking zone 3a, ensuring complete washing of the latter.
Similarly, during the rinsing step, the flow of rinsing liquid that traverses the second opening 14 enters the second flow distributor element 28 and, interacting with the flow distributor device 31, it is partially diverted upwards and partially downwards, being distributed substantially evenly in the cooking zone 3a, ensuring effective rinsing of the latter.
In Figure 5, a third flow distributor element 36 is illustrated that comprises a parallelepiped-shaped body 37 consisting of a lower part 37a and an upper part 37b connected together by two uprights 37c. Between the two uprights 37c, a passage 38 is defined through which the first flow of washing, or rinsing, liquid can pass, The body 37 is provided with a chute 39 tilted downwards, placed in a lower zone of the passage 38 and connected to the lower part 37a of the body 37.
The first flow of washing liquid, after traversing the second opening 14, enters the third flow distributor element 36 through the passage 38, is conveyed from the chute 39 to the inside of the cooking zone 3a and is distributed substantially evenly inside the cooking zone 3a, ensuring complete washing of the latter.
Similarly, during the rinsing step, the flow of rinsing liquid that passes through the second opening 14 enters the third flow distributor element 36 and is conveyed from the chute 39 to the inside of the cooking zone 3a so as to ensure effective rinsing of the latter.
In Figure 6, fixing of the second flow distributor element 28 to the tubular conduit 9 is illustrated.
The second flow distributor element 28 is hooked with the first hooking elements 26 to a crosspiece 42 provided in said second opening 14, and with the second hooking means 27 to the lower edge 22 of the second opening 14, so as to obtain stable fixing of the second flow distributor element 28.
Fixing the first flow distributor element 23 and the third flow distributor element 36 to the tubular conduit 9 is made in an identical manner to fixing of the second flow distributor element 28, disclosed above.

Claims

Oven (1) for cooking food provided with a washing system, said oven comprising a cooking chamber (3) divided by a wall (15) into a cooking zone (3a), in which said food is cooked, and into a heating zone (3b) in which air is heated and/or steam is produced to be sent to the cooking zone (3a), characterized in that said washing system comprises a supplying and distributing assembly comprising a supply chamber (6) that is suppliable with a washing liquid in a washing procedure for washing said cooking chamber (3), with water in a rinsing procedure for rinsing said cooking chamber (3), and with water for generating steam during cooking of the food, said supplying and distributing assembly further comprising a distributor element (9, 10) configured for distributing said washing liquid, or said water, both in said cooking zone (3a) and in said heating zone (3b), said supply chamber (6) communicating with said distributor element (9, 10) through a first opening (13).
Oven according to claim 1, wherein said distributor element (9, 10) comprises a tubular conduit (9), a first end (18) of which communicates with said opening (13) and a second end (19) of which, opposite the first end (18), terminates with a chute (10) oriented towards a suction zone (5) of a fan (11) arranged in said heating zone (3b), said tubular conduit (9) being further provided with a second opening (14) communicating with said cooking zone (3a).
Oven according to claim 1, or 2, wherein said supply chamber (6) is provided with a bottom (21) tilted by an angle (α) with respect to a longitudinal axis (A) of said tubular conduit (9), the size of said angle (α) being comprised between 30° and 60°, in which in particular the size of said angle (α) is 45°.
Oven according to claim 2, or 3, wherein a lower edge (22) of said second opening (14) lies on a plane containing said bottom (21), or above said plane, at a distance therefrom that is not greater than 20 mm.
Oven according to any preceding claim, wherein said washing liquid, in said washing procedure, is delivered into said supply chamber (6) at a flow rate comprised between about 10 1/min and about 20 l/min, at a supply pressure comprised between 0.4 bar and 0.6 bar, in which in particular the flow rate of said washing liquid is equal to 15 l/min, at a supply pressure of 0.5 bar.
Oven according to any preceding claim, wherein said water, in said rinsing procedure, is delivered into said supply chamber (6) at a flow rate comprised between about 10 l/min and about 20 l/min, at a supply pressure comprised between 0.4 bar and 0.6 bar, in which in particular the flow rate of said water is equal to 15 l/min, at a supply pressure of 0.5 bar.
Oven according to any preceding claim, wherein said supply chamber (6) is suppliable with said washing liquid by a first supply conduit (7) and with water by a second supply conduit (8).
Oven according to any preceding claim, wherein in said second zone (3b) a heating element (16) is arranged.
Oven according to any preceding claim, wherein in said suction zone (5) of the fan (11) a nebulizing element (20) is arranged.
Oven according to any preceding claim, wherein said supply chamber (6) is supplied with water, to produce steam during cooking of said food, at a flow rate comprised between 0.10 l/min and 0.20 l/min, in particular at a flow rate of 0.15 l/min.
Oven according to any one of claims 2 to 10, further comprising a flow distributor element (23; 28; 36) that is arranged inside the cooking zone (3a), at said second opening (14).
Washing system according to claim 11, wherein said flow distributor element is provided with a first pair of hooking elements (26) and with a second pair of hooking elements (27), in which said second opening (14) is provided with a crosspiece (42).
Washing system according to claim 11, or 12, wherein said flow distributor element (23) comprises a parallelepiped-shaped body (24), with a cage-shaped structure (25) that extends on three adjacent sides of said body (24) and is open at a fourth side of said body (24).
Washing system according to claim 11, or 12, wherein said flow distributor element (28; 36) comprises a parallelepiped-shaped body (29; 37) consisting of a lower part (29a; 37a) and an upper part (29b; 37b) connected together by two uprights (29c; 37c), between said uprights (29c; 37c) a passage being defined (30; 38) through which a first flow of washing, or rinsing, liquid can pass.
Washing system according to claim 14, wherein said flow distributor element (28) comprises a flow distributor device (31) that in turn comprises a first chute-shaped part (32) that widens towards the outside of said body (29), a second part (33) connected to an end (40) of said first part (32) facing the outside of said body (29), said second part (33) curving upwards, and a third part (34) connected to an end (41) of the second part (33) opposite said end (40) of the first part 32, said third part 34 being tilted upwards, said second part (33) and said third part (34) being provided with holes (35), or in which said flow distributor element (36) is provided with a chute (39) tilted downwards, placed in a lower zone of the passage (38) and connected to the lower part (37a) of the body (37).