Automatic self-contained ice cube machine
BACKGROUND AND SUMMARY OF THE INVENTION 
     The present patent for industrial invention is related to an automatic machine for the production of ice cubes, independent of any connection with the water system, made especially for household use, offices or small establishments. 
     Many types of automatic ice cube machines are known, made to be installed in public places, such as bars, restaurants, hotels and such, capable of a continuous ice cube production: all these machines require a continuous in- and outflow of water, their operation depending on a continuous cycle of an influx and discharge flow of water to a refrigerator; the above indicates therefore, the necessity of a connection with the general water system, and therefore the installation of a permanent kind, with resulting sensitive problems for home use, small establishments, offices, caused by the machines themselves. The machines known are moreover costly, and therefore not desirable for the above uses. 
     Consequently, the aim of this discovery is to furnish an ice cube machine that is completely free and independent of any water connection and that would be inexpensive, so that it could be used as a household appliance, in offices and small establishments. 
     The automatic machine for making ice cubes, according to the invention, has attained these aims because it furnishes a water tank able to contain a larger quantity of water than that necessary for one cycle of ice cube production, connected to the freezing units through means that can produce a continuous cycle of water between the water tank itself and these freezing units. 
     To be more specific, the machine invented is of the kind in which the freezing units are constituted of many small inverted cups connected to an evaporator and overhanging devices able to spray the water to be frozen into said small cups; the above-mentioned water tank is therefore connected to the spraying parts by means of a small duct connected to a pump immersed in the water tank itself, while a small discharge container collects the unfrozen water which is conveyed through a discharge duct, back to the water tank. 
     Another characteristic of the invention is that, in order to accelerate the cycle of production, the water tank is built in two compartments connected with each other at the bottom by a small opening, one of the parts having a capacity substantially equal to the quantity of water necessary for one or more cycles of production, the emission pump and the small discharge duct are immersed in this compartment, within which, during each cycle of production, a progressive cooling of the water takes place. 
     The spraying devices are furthermore built in such a way as to avoid the clogging of the spray tips through calcium deposits, possible particularly because there is no continuous renewal of water, as there is in conventional machines. Special devices are furthermore used to facilitate the easy access to various components for maintenance and cleaning especially. 
     These and further characteristics of the invention emerge from the following description, relating to a preferred way of illustrating the discovery--to give examples rather than set limits--in the figures of the drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 illustrates a view in perspective of the entire ice making machine invented; 
     FIG. 2 illustrates a cross section according to II--II in FIG. 1; 
     FIG. 3 illustrates a cross section according to III--III in FIG. 1; 
     FIG. 4 illustrates a plan view of the water tank of the invention; 
     FIG. 5 illustrates a section according to V--V in FIG. 4; 
     FIG. 6 illustrates in a front view the detail of the spraying and freezing unit according to the invention; 
     FIG. 7 illustrates the spraying unit according to the invention seen from above; 
     FIG. 8 illustrates the section according to VIII--VIII in FIG. 6; and 
     FIG. 9 illustrates in outline the regulating device of the refrigerator unit, according to the findings, in the inversion phase of the cycle. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In reference to the figures cited, the ice cube machine, according to the invention, is a compact mobile container, generically indicated at 1, having an upper small disappearing door in front 2, as well as a small lower door 3. 
     The interior delimited space of the movable container 1, is divided into an upper compartment 4, thermically insulated, constituting the cell for the production and gathering of the ice cubes, and into a lower compartment, called compartments because they are acessible from the outside and the front, respectively through the small doors 2 and 3. 
     Within the lower compartment 5 are located the compressor 6, the condensor 7 joined to the ventilator 8, in themselves conventional, and also a removable water container that will be described in detail later, placed so that it will be accessible from the outside, through the front of the appliance 1. In the lower compartment 5 is also the pump unit generically indicated by 10. 
     The upper compartment 4 is delimited by a box-like body 11 constructed of thermically insulating material, it contains the evaporator 12, joined to a number of small inverted cups 13, to constitute the refrigerator, the spraying unit, generically indicated by 14, and it also determines the tub 15 to receive the ice cubes; the ducts 16 and 17, respectively for intake and outflow, connect the spraying unit 14 to the water container 9, the intake duct 16 being connected to the pump unit 10, immersed in the water container itself. 
     The water container 9, with a capacity large enough to hold a greater amount of water than that necessary for the production of one cycle of ice cubes, is illustrated in detail in FIGS. 4 and 5; this container is constructed in the form of a box 90, made of thermoinsulating material, divided in two sectors, respectively 91 and 92, by a diaphragm 93, also made of thermoinsulating materials; the sectors 91 and 92 are intercommunicating through a small hole of communication 94, located next to the hole in the water container itself, on the diaphragm 93. Sector 91 has such a capacity that it is able to receive a quantity of water greater than that necessary for a cycle of production by the machine, while sector 92 is destined to receive the rest of the water that remains. 
     The water container 9 also has an upper lid 95 (visible in FIG. 5) provided with a protrusion 96, permitting the filling of the container itself with water, by means of a conventional pitcher or bottle, avoiding thus the necessity of removing the water container from its place and removing only the lower door 3. On the other hand, the possibility to remove the water container 9 allows its periodical removal with great ease for cleaning purposes with running water which is advantageous. 
     The spraying unit 14, illustrated in detail in FIGS. 6, 7 and 8, is formed by assembling a lower box of distribution and discharge 140 and of an upper element 141 carrying the spraying elements 142 and it is also provided with an upper chamber 143 to house the evaporator 12 and the small cups 13. 
     The box of distribution and discharge 140, made en bloc of stamped plastic, is formed in the shape of external circular discharge room 144, provided with a small orifice 144&#39;, and of an inner duct 145 of extremely reduced dimensions, provided with a small discharge orifice 145&#39;. 
     The upper element 141, also made in one piece of stamped plastic material, has three vertical walls, forming at the top a step creating the aforementioned seat 143, and an inclined element 146 presenting a number of slits 146&#39;, connecting the upper space to the discharge room 144, and also the two sprayers 142 in the shape of a semi-spheric dome and provided at the top with an opening 142&#39; with cylindrical section and considerable diameter; the surfaces delimiting the sprayers 142 define, within the tube 145 determined by the joining of the receiving and discharge box 140 with the upper element 141, two walls 147 that delimit two openings 148, the function of which will be described later. 
     The freezing unit, formed by joining the small copper cups 13 to the serpentine evaporator 12, is in itself of a conventional type, except that a special control is connected to it that is able to reverse the cycle of ice production, illustrated schematically in FIG. 9; a thermostat 18 is connected to a sensor 19, covered with thermically insulated material 19&#39;, set in direct contact with each one of the small copper cups 13; since it is possible to determine beforehand and empirically the temperature of the small copper cups 13 to which the complete formation of an ice cube corresponds, during a normal cycle of refrigeration, knowing the isolating power of the material 19&#39;, it is therefore possible to preset the thermostat 18 in such a way that it will control the reversal valve of the cycle 20, predisposed to determine the dropping of the formed ice cubes, in a direct manner: thus the necessity which exists in conventional techniques, to connect a timer to the thermostat, does not exist and therefore there is a reduction in cost and a better guarantee for the correct functioning of the machine. 
     The operation of the machine and its most important phases and characteristics are illustrated herebelow: 
     The machine is installed by simply plugging it into the electrical circuit, without having to use any water connection: then the user removes the lower door 3, reaches the water tank 9, fills it with water through the opening 96 with a pitcher, a bottle or any other container. The machine is therefore started with a conventional electrical switch that starts the compressor 6, the fan 8 and the feeding pump 10: the conventional cycle of refrigeration is thus started, while the pump 10, immersed in sector 91 of the water container 9, feeds the water, through the duct 16, to the distribution tube 145, thanks to the presence of the walls 147 and the tangential arrangement of the openings 148, the water penetrates into the sprayers 142 in the direction indicated by arrows F and F&#39;, and it will be sprayed toward the small cups 13 in a whirling motion, in order to achieve an even distribution and to limit the force of the spray against the walls of the cups 13 themselves. The water not immediately frozen falls therefore into the ring-shaped discharge box 144, through the slits 146&#39;, and is then carried through the small duct 17, into the same sector 91 of the water container 9 . Continuing the cycle, the progressive forming of the ice cubes is brought about, during the separation of the water contained in sector 91 of the water container, from the leftover mass of water, an acceleration of the production cycle itself is allowed, bringing about a progressive cooling off of that mass of water; however, the exchange is now made, by virtue of the principle of communicating vessels, through the connecting opening 94 between the two sectors 91 and 92 of the water container 9. 
     When the ice cubes are made, the thermostat 18 determines as previously illustrated, the reversal of the refrigeration cycle, in order to allow the cubes formed in the cups 13 to detach themselves, small cubes, which, sliding over the inclined surface 146, are gathered in the thermically insulated container 15. When the cubes have fallen out, the cycle begins again, and is repeated until there is no more water in the water container 9, being interrupted by a conventional hydrostat (not illustrated) eventually furnished and immersed within the water container 9. 
     The preceding description refers particularly to a machine with inverted cups, but it is evident how, with its original fundamental characteristics, and in particular with the self-contained water installation, thanks to the water container 9, the sphere of the present patent is not limited to a particular application, but comprises also the application to ice makers of the chute type.