Automatic humidification system for the dispensing heads of dosing machines for fluid products

Abstract

A humidification system for a dispenser head (14) of a dosing machine (10) for a fluid product, wherein the dispenser head (14) comprises a closing device (20) comprising a cup (27) which can be moved between a distal inoperative position and an operative position in which the dispenser head (14) is isolated from the environment. The humidification system automatically generates a humid environment in the cup (27) in a proximal position of the closing element (20) by means of a Peltier cell (32) inserted in a forced flow duct (29) of ambient air. The water condensed / frosted from the Peltier cell (32) is automatically supplied from a collection tank (33) to the cup (27) of the closing element (20) via a control unit (41).

Description

Technical Field

[0001] The present invention generally relates to dosing machines for dispensing products such as dyes for paints or the like.

[0002] More precisely, the invention relates to a dispensing head for such a dosing machine and has been developed with particular regard to its application in the dispensing of dyes for the preparation of paints. In the following description, reference will be made to this particular field of application, without however loss of generality. Background Art

[0003] A dosing machine for dispensing dyes for preparing paints generally comprises a plurality of containers containing the respective dyes, which are connected to a single dispensing head by corresponding pipes in the case of so-called "synchronous machines". A plurality of metering pumps feed the metered amounts of dye from the containers to the dispensing head, which generally comprises a plurality of nozzles with vertical axes parallel to one another, which are open at the lower end and are enclosed in a tubular member with an open lower edge.

[0004] The dispensing of dye from the nozzle of the dispensing head is usually discontinuous. At the end of dispensing, elongated dye drops are formed, which protrude from the lower end of the nozzle of the dispensing head: for the correct operation of the dosing machine, these dye drops need to remain in a fluid state and not harden.

[0005] In order to avoid or limit the risk of hardening of the dye droplet at the lower end of the nozzle of the distribution head, the quantitative machine can be equipped with a closing device, which closes the lower end of the distribution head when the dye is distributed. In this way, the area around the lower end of the nozzle of the distribution head is isolated from the external environment, and the drying of the dye droplet caused by being exposed to the air is reduced. The sealing in the contact between the lower end of the tubular member of the distribution head by closing element and the distribution head, and the sponge soaked in the liquid provided by the closing element inside, can improve the quality of isolation. When the closing element is applied to the distribution head, this allows the maintenance of a humid environment in the area of ​​the distribution head, so as to further hinder the drying of the dye droplet.

[0006] A solution of this type is described and illustrated by the same applicant in Italian Patent Application No. 102019000007192, not published at the filing / priority date of the present application, according to which the closing element is movable relative to the dispenser head according to a combined rotational-translational movement.

[0007] In order to reduce the risk of drying of the droplets, it has also been proposed in European patent EP2745943B1 to provide a cooling system for the nozzle of the dispensing head so as to maintain the dew point state of the liquid present in the nozzle, so as to keep them in a moist state and thus avoid drying. According to this solution, a cooling element is provided, which is in cooling contact with at least one end portion of the dispensing head.

[0008] Since this solution is applied directly to the dispensing head, it is relatively complex and its functional effect does not seem to be entirely satisfactory. Summary of the invention

[0009] The purpose of the present invention is to make available a humidifying system for the dispensing heads of machines for dosing fluid products, in particular (but not only) dyeing machines, which allows automatic humidification of the nozzles of the head, significantly reducing the likelihood of drying of the metered product, without having to apply it directly to the dispensing head.

[0010] Another object of the present invention is to provide a humidification system which is relatively simple, practical and capable of automatic operation in a reliable and safe manner.

[0011] This object is achieved according to the invention by a humidifying system having the features defined in claim 1 .

[0012] The claims form an integral part of the disclosure related to the invention provided herein.

[0013] One of the characteristic aspects of the humidification system according to the invention is that it is operatively associated with a cup of a closing element that is movable relative to the dispensing head between a non-operating distal position and a proximal operative position in which the dispensing head is hermetically sealed and isolated from the surrounding environment. The humidification system according to the invention is designed to automatically generate a humid environment inside the cup of the closing element when the closing element is in the proximal position, and advantageously comprises cooling means consisting of a Peltier cell and a supply circuit for condensed water from the Peltier cell into the cup of the closing element. The activation and deactivation of the supply circuit is automatically controlled according to the temperature and humidity of the ambient air, as well as the water level in the collection tank of the condensed water from the Peltier cell and the water level contained in the cup of the closing element. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Additional features and advantages of the present invention will become apparent from the following detailed description, given by way of non-limiting example only, with reference to the accompanying drawings, in which:

[0015] Figure 1 is a schematic perspective view of a dosing machine equipped with a humidification system according to the present invention,

[0016] Figure 2 is a perspective view from below and shown on a larger scale of a dispensing head of a dosing machine with a humidifying system,

[0017] Figure 3 yes Figure 2 A front view of a partly sectional view,

[0018] Figure 4 is based on Figure 3 A partial perspective view of arrow IV,

[0019] Figure 5 yes Figure 4 A front view of the invention, shown on a larger scale and in partial section,

[0020] Figure 6 yes Figure 3 , shown on a larger scale and in partial section,

[0021] Figure 7 is a block diagram illustrating the operation of a humidification system according to the present invention. DETAILED DESCRIPTION

[0022] First reference Figure 1 , a dosing machine which may be suitable for dispensing a quantitative fluid product (such as a dye for preparing a paint). The dosing machine 10 comprises, in a known manner, a carrier 12 which houses a plurality of containers ("tanks") for different dyes, which are connected to corresponding pipes via corresponding metering pumps (not shown).

[0023] The pipes from the various containers of the dosing machine 10 are connected to a dispensing head 14 in which a plurality of vertically oriented nozzles are arranged in a known manner and to a metering pump. The nozzles of the dispensing head 14 are enclosed in a tubular member 16 having an open lower edge 17 ( Figure 3 and 6 ).

[0024] A base 18 is provided below the dispensing head, a container is placed on the base, and the dye dispensed by the dispensing head 14 is poured into the container each time.

[0025] A closure device 20 is operatively associated with the dispensing head 14, the closure device being configured to isolate the lower end of the nozzle of the dispensing head 14 from the external environment at the end of each dye dispensing step.

[0026] The closure device 20 is described and illustrated by the Applicant in the aforementioned Italian Patent Application No. 102019000007192: in simple terms, it comprises a fixed support 22 containing an electric unit for moving a closure element 25 supporting a cup 27 with its opening upwards. The closure element 25 is carried by an arm 23 and can be moved angularly and vertically relative to the dispenser head 14 between an open distal position and a closed proximal position, as shown. This actuation assembly will not be described in detail here: for the purposes of the present invention, it is sufficient to specify that it is able to perform a combined movement of vertical translation and rotation of the arm 23 and therefore of the closure element 25 and of the cup 27. In this proximal closed position, the upper surface of the closure element 25 is sealingly engaged against the lower edge 17 of the tubular member 16 by means of an annular seal 26, so that the cup 27 is isolated from the external environment and is arranged below the nozzle of the dispenser head 14.

[0027] According to a unique feature of the present invention, the cup 27 defines a chamber configured to contain water produced by condensation at a temperature equal to or less than the dew point of the ambient air. Thus, when the dispensing head 14 is sealed by the closure device 20, the humid environment generated inside the sealed volume defined between the cup 27 and the tubular member 16 of the dispensing head 14 allows for increased protection of the dispensing head, since the possibility of drying out the product placed at the end of the various nozzles is further reduced when no dose is in progress.

[0028] The humidification system according to the invention (which will be seen to be automatic, although it can be replenished by manual refilling if necessary) envisages the intake of ambient air through one or more suction devices 28 positioned at the end of the forced flow duct 29 communicating with the suction nozzle 30.

[0029] The forced flow duct 29 has a cooling device inside, which is composed of a Peltier cell 32 and two heat sinks respectively arranged on the cold side and the hot side of the cell, wherein at least the cold sink 32a is passed through by the airflow generated by the suction device 28. The heat sink 32b can be passed through continuously by the same airflow that passes through the cold sink 32a, after the cold sink, due to the cooling effect of the airflow that hits the heat sink 32b, by previously passing through the cold sink 32a to obtain a specific efficiency advantage; or, according to an embodiment, the heat sink 32b can have its own independent ventilation. In any case, the heat dissipation generated by the heat sink 32b has the purpose of allowing the effective operation of the Peltier cell 32 and thus obtaining an appropriate amount of cooling for the cold sink. The function of the cooling system is to produce water by condensing or frosting the moisture from the ambient air sucked into the forced flow duct 29 onto the cold sink 32a of the Peltier cell 32. Frosting, instead of condensation, may be caused by the presence of environmental conditions that place the dew point below the freezing point of the local atmospheric humidity, or may be desired for functional reasons, even if the dew point is above said freezing point, in order to collect from the atmosphere a greater amount of water per unit time than is allowed by simple condensation; in the case of frosting, the working cycle envisages periodic closing steps of the Peltier cells 32 and therefore the cessation of the cooling action of the cold sink 32a, which also allows the liquefaction of the deposited frost due to the continuous forced ventilation of the ambient air through the forced flow duct 29. The collection of the water required for the humidification function is carried out by causing the water collected on the cold sink 32a to drip by gravity into a collection tank 33 below; this collection tank 33 acts as a reserve of water, in which water is always available and the extraction of water can be immediately activated / deactivated at any time, regardless of the time associated with the start / stop transient of the condensation / frosting process.

[0030] In order to carry out condensation / frost on the cold sink 32a, the radiator itself needs to reach and remain at a temperature not exceeding the dew point temperature (target temperature): therefore, the system can provide a temperature and relative humidity sensor 34 of the ambient atmosphere, which is positioned in the first part of the forced flow duct 29 and is designed to be able to continuously calculate the dew point; and a temperature sensor 35 of the target temperature, which is represented by the temperature of the cold sink 32a of the Peltier cell 32, so as to close the control loop and automate the cooling process.

[0031] In the collecting tank 33 there are a first water level sensor 36 and a second water level sensor 37 which respectively allow the reaching of a minimum water level and a maximum water level to be signalled in order to also automate the activation / deactivation process (suction and cooling) of the condensation system.

[0032] If necessary, the water stored in the collection tank 33 is pumped by the supply pump 38 to be delivered to the inside of the cup 27 of the closing element 25, which, in this step, is in the closed position proximal to the dispensing head 14 of the dosing machine 10. The delivery pipe 39 of the supply pump 38 feeds the water from the collection tank 33 to the cup 27 without affecting the temperature of the dispensing head 14, since the temperature of the water is substantially the ambient temperature, due to the more or less long residence of the water in the collection tank 33, and through the supply pump 38 and the associated pipes, all being exposed to the ambient temperature.

[0033] The cup 27 is also equipped with a level sensor system, which is essential for completing the automation of the system and is constituted by three electrodes protruding downwards from the dispensing head 14, namely a lowest level electrode 40a, a common electrode 40b and a highest level electrode 40c: the common electrode 40b and the highest level electrode 40c protrude at different lengths and the lowest level electrode 40a protrudes at a length not less than the length of the common electrode 40b, and is configured so as to detect the highest and lowest water levels present inside the cup 27. The highest level electrode 40c has a shorter length, the lowest level electrode 40a is longer than the highest level electrode 40c, and the common electrode 40b has a length equal to or less than the lowest level electrode 40a. When the closing element 25 is in the proximal closed position of the dispensing head 14, the three electrodes obviously protrude at different depths inside the cup 27, thus resulting in immersion or exposure relative to the water present therein. The liquid acts as a conductor and thus opens or closes the circuit (at very low voltage) between the lowest level electrode 40a and the common electrode 40b and / or between the highest level electrode 40c and the common electrode 40b, depending on the level of liquid present in the cup 27.

[0034] The closed-loop control circuit of the cooling system according to the present invention is Figure 7 : the automatic control unit 41 activates (minimum detected liquid level) or deactivates (maximum detected liquid level) the supply pump 38 for conveying the liquid present in the collection tank 33 to the cup 27 of the closing element 25. When the water level in the collection tank 33 drops below a threshold, the activation of the air flow through the Peltier cells 32 by means of the suction device 28 is operated by the automatic control unit 41, possibly (depending on whether it is used for production water, the logic of cooling below the dew point or forced frost at the lowest temperature that can be reached by the system at maximum power is selected) according to the signals from the temperature and relative humidity sensor 34 and the temperature sensor 35. When the water level in the cup 27 detected by the sensor 40 in turn drops below a threshold, the automatic control unit 41 activates the supply pump 38.

[0035] In all the steps in which no dose is in progress and the closing element 25 of the dispensing head 14 is closed on the dispensing head itself, the humid environment thus created inside the cup 27 hinders the drying of the product to be metered stagnant in the nozzle of the dispensing head 14, due to the gradual and spontaneous evaporation of the water present in the cup, thus eliminating possible problems of clogging of the duct due to condensation or solidification of the product itself. The possible additional use of a heater, not shown, which is also integral with the dispensing head 14 and protrudes inside the cup 27 until it is immersed below the water level when the cup is closed under the dispensing head 14, can improve the system by accelerating the evaporation of moisture and reducing the time required to reach a satisfactory moisture content in the atmosphere inside the cup 27 itself.

[0036] A manual refill line 42 may be provided ( Figure 3 ) to allow possible auxiliary additives (such as disinfectants or anti-algae products) to be introduced into the collection tank 33, or to provide for manual refilling of additional water if necessary.

[0037] Finally, an optional version of the humidification system can be created that does not include a water condensation device. This optional version with a reduced degree of automation can be proposed to meet two possible additional needs:

[0038] The possibility of providing users with a cheaper version of the automatic humidification system, abandoning the automatic production of water from the atmosphere,

[0039] In the case of dosing machines, it is permitted to employ liquids other than water for automatic humidification, wherein the water would have an undesirable interaction with the product to be metered if drops of product fell into the cup 27 of the closing element 25 .

[0040] In both cases, humidification liquid can be manually added to the collection tank 33 via the manual refill line 42 .

[0041] Of course, the details of construction and of the embodiments may vary widely with respect to what has been described and illustrated, without thereby departing from the scope of the invention as defined by the following claims.

Claims

1. A humidifying system for a dispensing head (14) of a dosing machine (10) for a fluid product, in, The dispensing head (14) comprises a closing device (20), which comprises a cup (27) and a closing element (25) having an upper edge, wherein the closing element (25) is movable between a non-operating distal position and an operating proximal position relative to the dispensing head (14), wherein the upper edge of the closing element (25) is sealingly engaged with the lower edge (17) of the dispensing head (14), and the humidification system is designed to automatically generate a humid environment inside the cup (27) in the operating proximal position of the closing element (25), and comprises a cooling device, which comprises a Peltier cell (32) arranged in a forced flow duct (29) with ambient air, a collection box (33) for water condensed and / or frosted by the Peltier cell (32), a water supply circuit from the collection box (33) to the cup (27), and an automatic control unit (41) of the cooling device and the water supply circuit.

2. The humidification system according to claim 1, in, The cooling device comprises a suction device (28) of ambient air in the forced flow duct (29), a temperature and relative humidity sensor (34) of the sucked air, a temperature sensor (35) associated with the Peltier cell (32), and a first water level sensor (36) and a second water level sensor (37) in the collection box (33); wherein a liquid level sensor (40) of water in the cup (27) and a supply pump (38) for supplying water from the collection box (33) to the cup (27) are provided; the automatic control unit (41) is operatively connected to the suction device (28), the Peltier cell (32), the first water level sensor (36), the second water level sensor (37) and the liquid level sensor (40) of water in the cup (27), and is configured to enable the suction device (28) when the water level in the collection box (33) drops below a threshold value, and to enable the supply pump (38) when the water level in the cup (27) drops below a threshold value.

3. The humidification system according to claim 2, in, The water level sensor (40) in the cup (27) comprises a set of three electrodes, namely a corresponding lowest level electrode (40a), a highest level electrode (40c) and a common electrode (40b) carried by the dispensing head (14) and protruding into the cup (27) at different heights.

4. A humidification system according to any one of claims 1 to 3, in, The collection box (33) is provided with a manual refilling conduit (42).

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