EP1338552A1

EP1338552A1 - Carbonator with thermoelectric cooler

Info

Publication number: EP1338552A1
Application number: EP03003727A
Authority: EP
Inventors: Eric Gambaro
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-02-22
Filing date: 2003-02-19
Publication date: 2003-08-27
Also published as: ITMI20020358A0; ITMI20020358A1

Abstract

A saturator, particularly for dissolving carbon dioxide in water, comprising a casing (2) adapted to contain a coil (12) at least partially immersed in an ice bank generated by a thermoelectric refrigeration unit. The saturator comprises a Peltier cell (11), which constitutes the thermoelectric refrigeration unit and is associated with a diffuser (10) that is arranged inside the casing (2) and is connected to a heat sink (14) arranged outside the casing.

Description

The present invention relates to a saturator particularly for dissolving carbon dioxide in water.
Machines for dispensing still and carbonated chilled water have long been used in the catering industry.
Conventional machines generally use a saturator, to produce carbonated water. The saturator is a pressurized tank in which the water is atomized in an environment that is saturated with carbon dioxide.
A suction system is provided in the lower part of the tank, while a level regulator inside it controls a pump for introducing water in the tank. The saturator is generally made of stainless steel.
In order to obtain carbonated water that has a pleasant taste and does not go flat rapidly, it is necessary to work at temperatures between 5 and 8 °C and at pressures around 3.2 bar. The temperature is particularly important for obtaining the desired characteristics.
Since cooling water requires significant energy levels and at the same time regulations forbid the storing of water in tanks without a suitable bactericidal system, for hygienic reasons, there are basically three different methods for cooling water before introducing it in the saturator.
According to a first method, a coil and the saturator are placed inside an ice bank (double solid-liquid phase) generated by a conventional refrigeration circuit (compressor, condenser, evaporator). The ice, by melting, absorbs energy (latent heat of melting), which it draws from the surrounding environment, thus maintaining the double phase at a constant temperature.
In a second method, the coil and the saturator are embedded in an aluminum block, which is kept at low temperature by a conventional refrigeration circuit.
According to a third method, the coil is placed inside the saturator itself, where the carbonated water in this case also acts as a thermal flywheel. The temperature of the water is maintained by applying a refrigeration circuit to the outer walls of the saturator or by evaporating inside the saturator in a suitable stainless steel coil.
The above described conventional devices operate satisfactorily, but they also have drawbacks, including the high cost of the devices and of their operation.
Other important drawbacks include noise levels and space occupation, which together with the maintenance required and with the costs, relegate these machines to purely professional use in catering and do not allow their widespread domestic use.
The aim of the present invention is to provide a saturator, particularly for dissolving carbon dioxide in water, that overcomes the drawbacks of the cited prior art.
An object of the invention is to provide a saturator that allows to obtain a machine for dispensing refrigerated and carbonated potable water that is compact and economically advantageous.
Another object of the invention is to provide a device that does not require particular and complex maintenance.
Another object is to provide a device that is capable of reducing significantly sound pollution and atmospheric pollution.
This aim and these and other objects that will become better apparent hereinafter are achieved by a saturator, particularly for dissolving carbon dioxide in water, as claimed in the appended claims.
Further characteristics and advantages will become better apparent from the description of preferred but not exclusive embodiments of the invention, illustrated only by way of non-limitative example in the accompanying drawings, wherein the only figure is a schematic transverse sectional elevation view of the essential components of the saturator according to the invention.
With reference to the cited figure, the saturator according to the invention, generally designated by the reference numeral 1, comprises a casing 2, which is closed in an upper region by a cover 3 and contains a coil 12 that has a inlet 4, on the outside of the casing 2, and an outlet 9, inside the casing 2, which constitutes a sprayer of a per se known type.
The saturator 1 also comprises two level probes, respectively a maximum-level probe 5 and a minimum-level probe 6, adapted to detect the maximum and minimum levels of the water of the ice bank contained inside the casing 2.
The carbon dioxide is introduced in the device through an inlet 7, while a duct 8 constitutes the system for withdrawing carbonated water.
According to the invention, the device comprises a Peltier cell, schematically designated by the reference numeral 11, which acts as a heat pump, assisted by a diffuser 10 that is located inside the casing 2 and is connected to an external heat sink 14.
In a per se known manner, the water is fed into the coil, through the inlet 4, and is sprayed by the sprayer 9 into the environment, which is saturated with carbon dioxide, after being cooled by the ice bank provided inside the casing 2.
According to the invention, a thermal flywheel is formed inside the saturator by applying a single Peltier cell.
A double solid-liquid phase is in fact produced which increases considerably the thermal flywheel inside the saturator. The generation of ice, which provides the necessary latent heat of melting, is adjusted by acting on the power supply of the cell.
The Peltier cell, by utilizing the thermal dipole formed in a bimetallic part by the flow of direct current, acts as a heat pump.
The low power of the individual cell (50 W) would not allow to produce a conventional ice bank, much less the application to an aluminum block.
Any placement of the Peltier cell on the walls of the saturator would drastically decrease its effectiveness, since stainless steel is a poor heat conductor.
According to the present invention, the diffuser 10, appropriately shaped and arranged directly inside the saturator, draws heat to transfer it to the heat sink 14, which is arranged outside the insulation.
Preferably, the diffuser 10 is shaped like an inverted cone, as shown schematically in the figure, so as to prevent, during the standby step of the cell, the ice from separating and floating on the free surface of the bank.
Preferably, the diffuser 10 is made of a material having high thermal conductivity, and at the same time resistant to the corrosion of carbonated water caused by the presence of carbonic acid.
A preferred material for manufacturing the diffuser is aluminum externally coated with Teflon.
In practice it has been found that the invention achieves the intended aim and objects, a saturator having been provided which is capable of producing significant quantities of carbonated fresh water, eliminating the drawbacks of machines provided with a conventional refrigeration circuit.
The saturator according to the invention solves the problems of noise and pollution of conventional devices and is also less expensive and bulky.
Due to the advantages cited above, the saturator according to the present invention is particularly suitable for the production of devices also for domestic use.
The device according to the invention is susceptible of numerous modifications and variations, within the scope of the appended claims. All the details may be replaced with technically equivalent elements.
The materials used, as well as the dimensions, may of course be any according to the requirements and the state of the art.

Claims

A saturator particularly for dissolving carbon dioxide in water, comprising a casing adapted to contain a coil at least partially immersed in an ice bank generated by a thermoelectric refrigeration unit, characterized in that it comprises a Peltier cell, which constitutes said thermoelectric refrigeration unit and is associated with a diffuser that is arranged inside the casing and is connected to a heat sink arranged outside the casing.
The device according to claim 1, characterized in that said diffuser is made of a material having high thermal conductivity, and resistant to corrosion.
The device according to claim 1 or 2, characterized in that said diffuser is made of aluminum coated externally with Teflon.
The device according to one or more of the preceding claims, characterized in that said diffuser is shaped like an inverted cone.
The device according to one or more of the preceding claims, characterized in that said coil has an inlet outside the casing and an outlet inside the casing, which constitutes a sprayer.
The device according to one or more of the preceding claims, characterized in that it comprises two level probes, respectively a maximum-level probe and a minimum-level probe, adapted to detect the maximum and minimum levels of the water of the ice bank that is contained inside the casing.