ICE MOLD

Abstract: Ice mold, of the type comprising a tray (10) provided with a plurality of cavities (11) for ice formation, each two adjacent cavities (11) being separated by a corresponding tray portion (12), at least part of said tray portions (12) being provided with at least one window (20), which is dimensioned in order to allow the formation and the ascending passage of a convective air current between each two adjacent cavities (11).

Description: ICE MOLD Field of the Invention The present invention refers to an ice mold of the type provided with a plurality of cavities for making ice cubes and which is particularly produced in plastic material . Background of the Invention The molds for producing ice cubes and used in refrigerators and freezers usually have longitudinal and/or transversal rows of cavities or receptacles for the formation of ice cubes and which are dimensioned so that each may produce an ice cube having determined characteristics of shape and dimensions within a known standard, conventionally searched by the user. An ice mold construction known in the art is made of a metallic material, usually aluminium. This construction has some advantages, such as the rapid formation of ice, due to the high speed of heat exchange between the mold material, which is a good heat conductor, and the environment where said mold is placed, usually a portion of the evaporating plate of a freezing compartment. However, the constructions using a mold in a metallic material have some disadvantages, such as the easy adherence of the lower surface of the mold cavities to the adjacent surface of the evaporating plate, difficulty in dislodging the formed ice cubes from the molds, rigidity of the piece and cost of the product. Aiming at solving these problems, molds of plastic material have been developed. However, these constructions have some deficiencies, such as the low speed in which the ice cubes are formed, due to the reduced thermal conductibility of the plastic and also to the formation of an air cushion, which acts as a thermal insulator and affects the capacity of heat exchange between the confronting lateral walls of the cavities . Disclosure of the Invention Thus, it is an object of the present invention to provide an ice mold, which allows a higher speed of ice cube formation, regardless of the material with which the mold is made, particularly when this material is plastic. This and other objectives are achieved by an ice mold, of the type comprising a tray provided with a plurality of cavities for ice formation, each two adjacent cavities being separated by a corresponding tray portion, at least part of said tray portions being provided with at least one window, which is dimensioned in order to allow the formation and the ascending passage of a convective air current between each two adjacent cavities. Brief Description of the Drawings The invention will be described with reference to the attached drawings, in which: Figure 1 illustrates, schematically, an upper plan view of the mold of the present invention; Figure 2 illustrates, schematically, a lateral view of the mold of the present invention; and Figure 3 illustrates, schematically, a perspective view of the mold of figure 1; Description of the Illustrated Embodiment According to the present invention, the ice mold, which is preferably produced in a single piece and from plastic material, comprises a tray 10, which is substantially flat and provided with a plurality of cavities 11, downwardly projecting from the tray 10, each two adjacent cavities 11 being spaced from each ether by a corresponding tray portion 12, said cavities 11 being, for example, arranged in longitudinal and transversal rows in the tray 10, as illustrated. Each cavity has, for example, four lateral walls 13, converging at a base portion 14, inferior, which is seated onto a surface for heat exchange and ice formation, and an opening portion 15, superior, for extracting the ice formed inside each cavity 11. According to the present invention, at least part of the tray portions 12 is provided with at least one window 20, which is dimensioned in order to allow the formation and the ascending passage of a convective air current between each two adjacent cavities 11. According to the illustrated embodiment, each cavity 11 has an inverted frusto-pyramidal shape, with the base portion 14 being substantially flat and with the opening portion 15 having an area value, which is higher than but substantially close to the area value of the base portion 14. The provision of tray portions 12 with windows 20 allows the confronting lateral walls 13 of the cavities 11 to have a maximized heat exchange, since they avoid the formation of an insulating air cushion in this region, as it occurs in the known prior art constructions, and allows the passage of a convective ascending refrigerant air flow, which allows said walls to effect heat exchange as well . According to the present invention, in order to increase the heat exchange, without however significantly altering the dimensions and shape of the usual ice cubes, each cavity 11 has a depth calculated so as to correspond to about 70% the value of the smallest dimension of the opening portion 15, defining a dimensioning for the cavity 11 which results in an ice cube with a reduced height and enlarged horizontal dimensional parameters in relation to the usual ice cubes . In the case of ice molds in plastic material, in order to increase the speed of heat exchange of the cavities 11 of said molds with the freezing compartment into which the latter are placed, the present invention further foresees the construction of cavities 11 with reduced thickness, at least at its base portion 14, for example, of about 0,6 mm. The lateral walls 13 thereof may have a reduced thickness as well, or with an intermediate thickness value, situated between that of the base portion 14 and that of the tray portion 12.

Claims: CLAIMS 1. An ice mold, of the type comprising a tray (10) provided with a plurality of cavities (11) for ice formation, each two adjacent cavities (11) being separated by a corresponding tray portion (12), characterized in that at least part of said tray portions (12) is provided with at least one window (20), which is dimensioned in order to allow the formation and the ascending passage of a convective air current between each two adjacent cavities (11). 2. Ice mold, as in claim 1, characterized in that each cavity (11) has a base portion (14), inferior and substantially flat, which is seated against a surface, and an opening portion (15), superior, whose area value is higher than but substantially close to the area value of the base portion (14), in order to impart to the respective cavity (11) a substantially inverted frusto-pyramidal shape. 3. Ice mold, as in claim 2, characterized in that each cavity (11) has a depth corresponding to about 70% the value of the smallest dimension of the opening portion (15). 4. Ice mold, as in claim 3, characterized in that the cavities (11) are arranged in longitudinal and transversal rows in the tray (10). 5. Ice mold, as in claim 4, characterized in that it is made in a single piece. 6. Ice mold, as in claim 5, with the tray (10) being made of plastic material, characterized in that each cavity (11) has a reduced thickness at least on the base portion (14) thereof.

Inventors: DIEMER LOPES LUIZ ANTONIO, HERMES DE ARAUJO RODRIGO, DIEMER LOPES, LUIZ, ANTONIO, HERMES DE ARAUJO, RODRIGO
Applicants: MULTIBRAS ELETRODOMESTICOS SA, MULTIBRAS S.A. ELETRODOMESTICOS
Application year: 1999
Main classification: F25C1
IPC codes: F25C1