WO2015056063A1

WO2015056063A1 - Oven for the foodservice industry with a device for feeding the detergent to the washing system of the cooking chamber

Info

Publication number: WO2015056063A1
Application number: PCT/IB2014/001828
Authority: WO
Inventors: Moreno Zanchetta; Imazio OSCAR
Original assignee: Lainox Ali Spa
Priority date: 2013-10-17
Filing date: 2014-09-12
Publication date: 2015-04-23
Also published as: DE112014004758T5; ITTV20130170A1

Abstract

Oven for cooking food with a cooking chamber closable by a door vertically hinged with respect to the body of the oven, and with inside the cooking chamber at least one air recirculation fan; a heating device; controlled means of feeding, distribution, recirculation and removal of the detergent liquid in the cooking chamber; a control logic unit of the oven and of the washing system with a feeding device which comprises at least one tank with which a detergent in a removable cartridge is engaged, said tank being extractable like a drawer from said oven which includes level sensors or plug/cartridge presence sensors; a recirculation pump of the contained liquid; means for removing the sealing element of the cartridge and for the recirculation of the liquid in the tank; a water inlet and a connection for the drawing of the detergent liquid in said container by the washing/rinsing/decalcifying pump which is present in said oven.

Description

OVEN FOR THE FOODSERVICE INDUSTRY WITH A DEVICE FOR FEEDING THE DETERGENT TO THE WASHI NG SYSTEM OF

THE COOKING CHAMBER

[0001 ] The present invention relates to an apparatus for cooking food in the foodservice industry, in particular industrial ovens for cooking food, such as the ovens for restaurants and large kitchens, for example an electrical or gas oven of the convection or mixed type for cooking food, which is provided with an automatic washing system for the cooking chamber and the boiler, fed with liquid detergent by a drawer device with a refill cartridge.

Field of the invention

[0002] In the field of the foodservice industry there is the need to resort to equipment for cooking food, such as ovens, provided on the one side with a good thermal yield for a faster and more uniform cooking minimizing consumptions, but on the other side above all able to provide in one single integrated oven a good versatility of use according to the chef's growing and variable needs, for example the fact of being able to roast, braise, grill, brown or saute the food being cooked, and so on, not excluding the possibility to simultaneously treat various kinds of food, different by nature and size.

[0003] In principle, these ovens for the foodservice industry are large, and have a configuration of the coating structure or external body which is in the shape of a parallelepiped which on its inside comprises a cooking chamber. Said cooking chamber is accessible by means of a door that can be opened and vice-versa on the front of said oven, by means of conventional opening/closing means and inside there are dedicated components, such as at least one air recirculation fan, heating means and so on, which vary depending on the configuration of the oven. Finally, outside the oven, on the side of the front a control panel is provided, which by means of a logic unit interfaced with the user, manages all the functions of the oven.

[0004] One can reasonably agree that the cooking chamber is certainly one of the places inside which at the end of each cooking phase a large amount of dirt remains, which according to the number of cooking cycles tends to increase in quantity and consistency, collecting in the most hidden points, even solidifying in several layers. In the same way it is evident that the same oven after cooking with an operation cycle made for example for meat, afterwards is hardly used for a different food, such as fish. Therefore, one easily understands that the ordinary cleaning of the oven is an essential condition before activating a cooking cycle, and this on the one side to prevent food contamination by polybacterial agents that proliferate in dirt, on the other side in order not to alter the organoleptic characteristics of food. Said ordinary cleaning phase, which once was carried out manually, for a long time now has been carried out automatically, as a normal function of the oven, uniformly distributing some detergent inside the oven.

Prior art

D1 EP0892220A1 (Braun et al.) D2 DEI 00602004 (Mohr)

D3 EP2502542 (Tropfer at al.)

D4 CN202074580U (Zhengbin et al.)

[0005] For example, a short prior art search, although not in-depth, revealed some prior documents that represent a reasonable overview of the known applications.

D1 proposes an oven for the thermal treatment of food and methods for cleaning the internal space. The oven comprises a heated cooking chamber, which is closed by means of a door, also comprising fluid circulation means distributed within the cooking chamber, and with a lower end, which is closed by means of a valve. To carry out the cleaning some means are provided, for example some nozzles, which are intended to clean the internal space and which are fed by a detergent liquid. Moreover, it is provided with a control means for automatically controlling the washing procedure. The automatic control means control the circulation, the outlet closing valve placed on the bottom and the feeding device to clean the space of the cooking chamber with said detergent until a predetermined level.

D2 describes a cleaning system that comprises an internal chamber having a door and heated by a heating device, devices for the feeding and recirculation of the liquid in the internal chamber and the removal of the liquid from the internal chamber, and a control device joined to the devices to control the cleaning cycle. At least one support for a cartridge detergent is thermally and/or chemically activable releasing the detergent. The detergent is totally released without residues until the end of a cleaning cycle. Other aspects concern a cartridge for the cleaning system, in a kit as well, and a method for cleaning the internal chamber of an oven.

[0006] In recent years convection or combined (convection/steam) ovens have thus been provided, with increasing frequency, with systems for the automatic cleaning of the chamber and of the boiler. In the field of said systems, at present, among the types of detergent, rinse aid or decalcifying agent used to feed the washing cycles three categories can substantially be found: Liquid in a tank or container, Tabs, Cans/cartridges in a single-dose version. As to the liquid detergent (or rinse aid or decalcifying agent) it can be observed that it is normally contained in tanks from which, through a small tube connected to a pump with which the oven is equipped, it is drawn and used by the washing or decalcifying system, in a cycle managed by the logic unit of the oven. As an alternative, the product can first be poured into a container with an edge external with respect to the oven and thus drawn by the pump of the oven. In this case, too, the pump for feeding the delivery and recirculation means draws an amount of detergent suitable for the intensity of the washing or decalcifying operation. In the case of the solutions so-called in tabs, which derive from dishwashers, the detergent (or rinse aid or decalcifying agent) in the form of a tab must be introduced into the oven each time before the washing/decalcifying phase in an amount suitable for the intensity or type. In the last type of detergent (or rinse aid), in the single-dose version, it is essentially powdered and is contained in small cans in the form of cartridges, which are placed inside the apparatus before the washing or decalcifying phase. Upon removal of the plastic plug of the can, the content is released during the washing process once the water- soluble retaining seal, placed under the plastic plug, has dissolved. Also known are single-dose cartridges containing two components, for example both the detergent and the rinse aid, divided by an additional water-soluble seal placed midway across the can so that the release occurs in two different steps: in the first the first seal is dissolved and a component, which normally is the detergent, is released, while in the second step, following the dissolution of the second seal, the second component, normally the rinse aid, is released as well.

Closest prior art

[0007] A solution like the one which has just been described can be found in D3. In particular, it aims at providing a universal system for feeding and dosing a liquid treatment agent, in particular for cleaning, descaling or rinsing, with a concentrated powder, tab or liquid agent, in such a way as to feed and bring the dose to a treatment chamber, in particular a commercial or household dishwasher or even inside an oven for cooking food. One provides the use of a tightly sealed cartridge for use in multiple dosing, which contains a concentrated detergent in the form of powder or in the form of a tab or in a liquid or gel form, safe to be handled, transported and stored with a good simplicity of use. The distribution system comprises various functional areas and components, and in particular an opening portion for prearranging the treatment agent, a storage area adjacent to the opening portion from which the treatment agent is drawn in doses. Between the opening portion of the cartridge and the tank part there is a retaining device for preventing the uncontrolled non-dissolved or partially dissolved backflow in the detergent feeding area. The delivery means include an operating device for the release of the integrated product from a sealed cartridge. The dispenser comprises means for the circulation of fluid placed within the dissolution zone and an apparatus for the circulation of the fluid, which is placed inside the portion of space in which the treatment agent is drawn. Finally, the dosing device comprises a fluid inlet to fill the opening portion and the storage part. The fluid is usually used for filling with tap water and is provided with an overflow. The sealing device is placed between the opening portion and the storage part and comprises a structure permeable to the fluid, such as a screen, a fabric or a membrane or the like. The sealant aims at retaining the product until this is completely diluted in the solution, that is to say, it is sufficiently dissolved in the opening area. Another aspect of the solution is to provide a dosing that allows the feeding of the detergent in a provided concentration which is defined in it.

D4 describes an oven for cooking food, with an opening door with horizontal hinges, said oven comprising a cooking chamber, and under said cooking chamber, separate from the latter, a space that houses a frontally extractable drawer provided with a handle, by means of lateral sliding guides. The aim of said drawer, obtained in the lower part of the oven, is to keep the food cooked in the cooking chamber above at a controlled temperature and in a separate environment with respect to said cooking chamber.

Drawbacks

[0008] For the conventional user of the oven for cooking food in the foodservice industry the solutions of management of the washing phase by means of the detergent known in the prior art have various drawbacks. For example, in the case of the cooking equipment provided with the washing system that requires the detergent liquid in a tank or container, first of all there are some difficulties of transport of the detergent in containers. Secondarily, there is a certain danger in the handling phases in the pre-arrangement of the cooking apparatus, such as the replacement of the tank having to carry out the movement of the plug combined with the sucking tube, or alternatively in performing the operation of pouring the detergent into the container in correspondence of the edge of the oven. Finally, it is evident that the tanks, in addition to the difficulty of transport, are influenced by their encumbrance in the storehouse, which requires at least some suitable spaces.

[0009] As for the tabs, one can reasonably agree that there is a certain danger in the phase of insertion of the tabs into the apparatus, because, before being introduced, they must be extracted from their bag whose phase of removal requires the user to wear suitable protective clothes. A second drawback is related to the management of the washing system, which is onerous because before each washing/decalcifying cycle the operator must load into the apparatus a number of tabs of one or more kinds depending on the intensity or on the type of washing intended.

[001 0] Finally, some drawbacks can also be found in the single-dose solutions in cans/cartridges. From a practical point of view they have poor flexibility because each cartridge contains a determined amount of detergent/rinse aid, therefore the intensity of the washing process is necessarily predetermined and fixed. Moreover, as for the solutions in tabs, also in that case there is an onerous management due to the fact that the operator, before each washing must load into the apparatus a single-dose cartridge.

Short description of the object of the invention

[001 1 ] This and other aims are achieved by the present invention according to the characteristics as in the appended claims by means of an oven for cooking food in the foodservice industry wherein said oven includes a cooking chamber closable by a door which is vertically hinged with respect to the body of the oven, and with inside the cooking chamber at least one air recirculation fan; a heating device; controlled means of feeding, distribution and recirculation of the detergent liquid in the cooking chamber and with means for the removal of said liquid from said cooking chamber; a control logic unit of the oven and of the washing system with a feeding device that comprises at least one tank with which a detergent in removable cartridge is engaged and means for removing the cartridge sealant releasing the detergent that falls and is dispersed in the tank, wherein said tank is of the extractable drawer type placed in the lower part of said oven, and includes plug/cartridge level or presence sensors; a recirculation pump of the contained liquid; means for removing the sealing element of the cartridge that contribute to the recirculation of the liquid in the tank; a water inlet and a connection for the drawing of the liquid detergent in said tank by the washing/rinsing/decalcifying pump that is present in said oven.

Advantages and aims

[001 2] The proposed solution undoubtedly achieves various advantages and aims. With respect to the solutions that describe washing systems with removable cartridges or cans, the object of the present invention allows the carry out several washing cycles, without having to resort to the continuous replacement of the cartridge/can, it being possible to draw in a controlled way from a concealed and capacious controlled tank of detergent liquid. In the known solutions it has been observed that the dimensional configuration of the cartridges and of the mixing trays and their placement imply the usability of a reduced amount of detergent, which does not make it possible to change the washing cycles, changing their intensity. In the object of the present invention the fact of having a large-sized tank that contains the detergent liquid pre-arranged for the washing system, for several washing cycles, allows to adjust to taste the intensity, for example manually setting the phases of each washing cycle, that is to say, proceeding by means of a previously set programme that adjusts the washing phases and intensity, enabling a more accurate cleaning sanitization of the cooking chamber or of the boiler, in conclusion contributing to the best quality of the cooking of food.

[001 3] The particular configuration of the oven in its lower part also allows to house even more than one feeding device, in such a way as to be able to use a first feeding device that can also provide the destination by means of a cartridge in the form of a removable can with the cleaning or rinsing or decalcifying component intended to dissolve in water different from the one provided in the second and adjacent similar device, with which the washing system interacts by means of the control unit. These and other advantages will be clear from the following detailed description of at least one practical embodiment to be interpreted considering the enclosed schematic drawings.

Content of the drawings

Fig. 1 is a schematic sectional view of the feeding device of the detergent and/or of the rinse aid and/or decalcifying agent for the washing system in the oven object of the present invention;

Fig. 2 is a schematic view of the lower part of an oven for cooking that integrates the feeding device of Figure 1 ; Fig. 3 is another schematic view of the lower part of the oven for cooking as in Figure 2, but in the condition of tank of the feeding device, extracted, in a first operating condition.

Practical realization of the invention

[001 4] In an oven ( 1 0) for cooking food intended for the foodservice industry, (FIG. 2) there is a body that also acts as an external coating, having a parallelepiped shape, respectively made up of a back side of the oven, two parallel sides, a bottom, and one front (1 00). The front comprises the door that by means of the vertical hinge is hinged to the body of the oven (1 0), providing access to the cooking chamber.

[001 5] Inside the oven ( 1 0) the cooking chamber is obtained, which, closed by said door at the front (1 00) of the oven ( 1 0), along the perimeter, has a shape developing on three sides orthogonal to one another, respectively a back wall and two side walls, respectively a right and left wall. Separate from the side wall or from the back wall is a baffle so as to house in the intermediate area at least one recirculation fan that is moved by a motor placed in a space distinct from the cooking chamber, wherein said technical space is at a controlled temperature in such a way as to not influence the electronic and electromechanical components that manage the operation of the oven (1 0). In a different configuration of the oven, inside said space distinct from the cooking chamber, there may also be a boiler intended for steam production, which by means of a connection pipe is introduced into the cooking chamber. Finally, there are means for generating the heating of the cooking chamber or of the boiler, in such a way as to allow the heating of said cooking chamber by means of electrical resistors, heat exchangers with gas or steam from the boiler, or in modes combined with each other.

[001 6] Said oven (1 0) also comprises a washing system of the cooking chamber and/or of the boiler, and is provided with means intended to sprinkle or distribute the treatment liquid that can be a detergent, rinse aid or decalcifying agent, for example in said cooking chamber. A washing pump carries out the controlled feeding of said means intended to sprinkle or distribute for example the detergent liquid, said means in a case in the form of nozzles, and draws said detergent liquid by means of a feeding device of the detergent liquid (1 1 0) (FIG. 2) which is integrated in said oven (1 0). A circuit of discharge from said cooking chamber and of recirculation of the detergent liquid is further provided in said oven (1 0).

[001 7] Said feeding device of the detergent liquid (1 1 0) comprises at least one tank (1 1 1 ) (FIG. 1 ) in the form of a drawer that is placed in the lower part of the oven ( 1 0) in an area between the cooking chamber and the top of the oven itself (1 0). The configuration of the tank (1 1 1 ) is such that it can be extracted manually in a controlled way from the part underlying said oven (1 0), in such a way as to protrude in an overhanging way with respect to the front ( 1 00) and if necessary be removed for maintenance. In a further preferred solution (FIG. 2 and 3) there may be a second tank (1 1 1 ) next to said first tank and similarly configured as described hereinafter. The function of the tank (111 ) is to allow the dissolution in the water contained in said tank (111) of the concentrated powder (200), which is contained in a large container can (210). In this case, the concentrated powder (200) can be made up of the detergent, rinse aid or descaling/decalcifying agent only or also combined in proportions between each other. Said can (210) in the form of a cartridge is made in such a way as to have, under the removable plastic plug, a seal of water-soluble material (211 ). Such a solution allows to have a stock of diluted product on hand for a more or less long period depending on use.

[0018] The tank-dissolver (111) which acts as a temporary supporting element of the can/cartridge (210) has a seat (112) shaped to receive the neck (212) of the can/cartridge (210). In more detail, said seat (112) has along the perimeter wall (113) of inlet of the neck (212) of the can/cartridge (210) a coupling, for example of the threaded type or of the bayonet type which cooperates with a corresponding coupling which is obtained in the perimeter area of the neck (212) of the can/cartridge (210) in such a way as to provide a stable fixing. When the can/cartridge (210) is removed from the tank (111), the seat (112) is closed by a plug (120) which prevents the liquid contained inside the tank (111) from coming out.

[0019] Inside the tank (111) in the part just underlying the inlet seat (112) there is a filter (114) which being placed below the coupling of the can/cartridge (210) prevents the recirculation of the powder (200) once the seal (211) has been removed, allowing the dispersion of the product only when it is dissolved. More particularly, inside said filter (114) there is a spraying nozzle (118) which is made up of several spraying holes so that some sprays on the one hand dissolve the retaining water-soluble seal (211) and on the other hand contribute to the recirculation of the so obtained detergent liquid through the filter (114) above all when the powder (200) contained in the can/cartridge (210) in the first phase falls downwards and is held by said filter (114).

[0020] Level sensors (116, 117) placed inside the tank (111) detect the level of the liquid, at least corresponding to the minimum and maximum capacity, present inside the tank (111). Furthermore, some other sensors (115) have the function of detecting the presence of the plug (120) or also of the can/cartridge (210) and are placed in the area of the inlet seat (112). In this way the information of said sensors (115, 116 and 117) is transferred to the control unit of the washing system which is provided by the logic unit of the oven (10) interfaced with the operator by means of a control panel placed on the front (100) of the oven (10).

[0021] A recirculation pump (130) of the liquid contained in the tank (111) which draws the liquid from inside said container (111) and which simultaneously feeds the nozzle (118) is managed always inside said tank (111). For the purpose of enabling the filling of the tank (111) with the water into which the powder product (200) contained in the can/cartridge (210) will then be dissolved, there is a water inlet manifold (140) operated by a valve (141), managed by the control unit of the washing system of the oven (10). Finally, a connection (150) is provided for the drawing of the diluted detergent liquid by the washing/rinsing/decalcifying pump (151) present in said oven (10)

[0022] Operatively, at the first use, the operator will have to extract in a sliding way the tank drawer (111), remove the plug (120) from the inlet seat (112) and then apply at the inlet seat (112), by screwing or interlocking, the can/cartridge (210) which contains the powder product to be diluted (200) and activate the washing/rinsing/decalcifying cycle. Once a first cycle, for example of washing, has been carried out in such a way that the product contained in the can/cartridge (210) has been completely dissolved in the liquid contained by the tank (111), the can/cartridge (210) is removed and the respective plug (120) is applied at the inlet seat (112), and then the drawer tank (111) is closed by pushing it manually until its closing in a hidden condition.

[0023] Every time there is the impulse by the control unit of the washing system to draw the detergent liquid from the tank (111), the system, should it detect by means of the level sensor (117) that said tank (111) is empty, will require to apply a new can/cartridge (210) and will activate a new sequence of dissolution of the product. In this case, by means of the connection (140) and of the pump (141 ), it will fill with a suitable amount of water the tank (111) until reaching the high level detected by means of the level sensor (116), and then will begin to make it recirculate through the recirculation pump (1 30) pushing it in the spraying nozzle (1 1 5) in order to dissolve first the water-soluble seal (21 1 ) and then the powder (200) that, contained in the can/cartridge (21 0), will fall down into the filter ( 1 1 4).

[0024] After the period of time designated for the complete dissolution of the powder (200), the control unit of the washing system will give consent to the drawing through the connection (1 50) by means of the pump (1 51 ) of the diluted product for the washing/rinsing/descaling cycle carried out by means of the feeding circuit of the distribution nozzles inside the cooking chamber and/or the boiler of the oven (1 0).

[0025] Every time the control unit of the washing system requires to remove the can/cartridge (21 0) and replace the plug (1 0), the oven (1 0) will have at its disposal a sufficient amount of product for a number of treatment cycles according to the type and intensity. After reaching the low level detected in the tank (1 1 1 ) by means of the sensor (1 1 7) the control unit of the washing system, knowing the residual amount, will allow to activate the cycle or the cycles compatible with said residual amount, otherwise it will require to insert a new can/cartridge (21 0).

Reference

(1 0) oven

(1 00) front [110) feeding device of the treatment liquid [111) tank

[200) concentrated powder

[210) container can

[212) neck of the can/cartridge

[112) inlet seat

[113) perimeter inlet wall

[120) plug

[114) filter

[211) seal

[118) spraying nozzle

[116, 117) level sensors

[115) presence sensor

[130) recirculation pump

[140) water inlet manifold

[141) valve

[150) a liquid drawing connection

[151) washing/rinsing/decalcifying pump

Claims

1 . Oven for cooking food in the foodservice industry wherein said oven (1 0) comprises a cooking chamber closable by a door which is vertically hinged with respect to the body of the oven ( 1 0), and with inside the cooking chamber at least one air recirculation fan; a heating device of said cooking chamber; controlled means of feeding, distribution and recirculation of the treatment liquid in the cooking chamber of the detergent, rinsing or decalcifying type, and with means for the removal of said liquid from said cooking chamber; a control logic unit of the oven and of the washing system which draws the treatment liquid dissolved in water by means of a can in the form of a removable cartridge which contains the product to be dissolved, characterised in that the feeding device (1 1 0) of the treatment liquid comprises at least one tank (1 1 1 ) for a water- soluble product in a removable cartridge (21 0) and means (1 1 5, 1 30) intended to remove the sealant (21 1 ) of the cartridge releasing the detergent (200) which falls into the tank (1 1 1 ) held by a filter (1 1 4), wherein said tank (1 1 1 ), is of the extractable type in the form of a drawer and is placed at the front (1 00) in the lower part of said oven (1 0) in a zone between the cooking chamber and the top of said oven ( 1 0).

2. Oven for cooking food with a feeding device of the treatment liquid, according to claim 1 , characterised in that it comprises level sensors of the treatment liquid (1 1 6, 1 1 7) and presence sensors (1 1 5) of the plug (1 20) or of the can/cartridge (21 0); a recirculation pump (130) of the liquid contained in the tank (111), means (115) intended to remove the sealing element (211) of the can/cartridge (210); a water inlet (140, 141) and a connection (150) for the drawing of the treatment liquid in said tank (111) by the washing/rinsing/decalcifying pump (151) which is present in said oven (10).

3. Oven for cooking food with a feeding device of the treatment liquid, according to claims 1 and 2, characterised in that inside the tank (111 ) in the part just underlying the inlet seat (112), there is a filter (114) in such a way as to prevent the recirculation of the powder (200) once the seal (211) has been removed, and wherein inside said filter (114) there is a spraying nozzle (118) fed by the recirculation means (130), which is made up of several spraying holes so that some sprays on the one hand dissolve the retaining water-soluble seal (211) and others contribute to the recirculation of the so obtained detergent liquid through the filter (114).

4. Oven for cooking food with a feeding device of the treatment liquid, according to the previous claims, characterised in that the control logic unit of the functions of the oven (10) comprises a control function of the washing system, which checks and coordinates the information it receives from the level sensors (116, 117) and from the presence sensor (115) of the plug (120), in such a way as to manage the activity of the recirculation pump (130), the water feeding pump (140, 141), the treatment liquid drawing pump (150, 151), said logic unit being prearranged to enable the change of the washing system, for several washing cycles, in such a way as to adjust intensity to taste.

5. Oven for cooking food with a feeding device of the treatment liquid, according to the previous claims, characterised in that the control logic unit of the functions of the oven (10), every time it receives the pulse by the control unit of the washing system to draw the detergent liquid from the tank (111), should it detect by means of the level sensor (117) that said tank (111) is empty, will require to apply a new can/cartridge (210) and will activate a new sequence of dissolution of the product, filling, by means of the connection (140) and of the pump (141) with a suitable amount of water the tank (111) until reaching the high level detected by means of the level sensor (116), and therefore will make the liquid recirculate through the recirculation pump (130) pushing it into the spraying nozzle (115) in such a way as to dissolve first the water-soluble seal (211) and then the powder (200) which, contained in the can/cartridge (210), will fall down into the filter (114), and furthermore wherein after the period of time designated for the complete dissolution of the powder (200), the control unit of the washing system will give consent to the drawing through the connection (150) by means of the pump (151) of the diluted product; said tank (111) having at its disposal a sufficient amount of product for a number of treatment cycles according to the type and intensity, in such a way that, after reaching the low level in the tank (111) detected by means of the sensor (117) the control unit of the washing system, knowing the residual amount, will allow to activate the cycle or cycles compatible with said residual amount, otherwise requiring to insert a new can/cartridge (21 0).

6. Method for feeding a washing system in an oven for cooking food, characterised in that, at the first use, the operator must extract in a sliding way the drawer tank (1 1 1 ), remove the plug (1 20) from the inlet seat (1 1 2) and then apply at the inlet seat ( 1 1 2), by screwing or interlocking, the can/cartridge (21 0) which contains the powder product to be diluted (200) and activate the washing/rinsing/decalcifying cycle; once a first cycle, for example of washing, has been carried out in such a way that the product contained in the can/cartridge (21 0) has been completely dissolved in the liquid contained by the tank ( 1 1 1 ), the can/cartridge (21 0) is removed and the respective plug ( 1 20) is applied at the inlet seat (1 1 2), then reclosing the drawer tank ( 1 1 1 ) by pushing it manually until its complete closing in a hidden condition.