Abstract:
An expresso machine has a hot water distributor and an adapter which is removably connectable to the distributor to receive hot water therefrom. A box is in turn removably connectable to the adapter and defines with the same an extraction chamber adapted to house a prefabricated coffee pod through which the hot water must pass on its way to an outlet of the box, thus brewing a portion of coffee.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a coffee machine. 
     More particularly, the invention relates to an espresso coffee machine. 
     Traditional espresso coffee machines, of the Italian type used in bars, restaurants and coffee shops, are constructed to brew coffee by passing hot water through a quantity of ground coffee which is placed into a filter inside a receptacle. 
     Removal of the receptacle, used coffee and filter, and reinstallation of the receptacle with new supplies, is not difficult but does require the services of an operator who must be paying attention to this work. In restaurants and similar establishments these operators are, however, often distracted by other demands which are made on them. This having been recognized, prefabricated pods of coffee have been developed which require no filter, no pouring, and no measuring, but are simply slipped into a chamber provided for them in the coffee machine. Unfortunately these pods, each of which equals one brewing measure and is formed by compressing ground coffee between two layers of water-permeable filter paper, cannot be used in the conventional coffee machines. The pods do not fit the receptacles of those machines and are only suitable for use in an extraction chamber of the type disclosed in U.S. Pat. No. 4,254,694. Nevertheless, in view of their advantages it would evidently be also desirable to be able to use such pods in conventional machines. 
     SUMMARY OF THE INVENTION 
     It is, accordingly, an object of the invention to provide prefabricated coffee pods which may be used in conventional coffee machines. 
     A more particular object is to allow the use of such coffee pods in conventional coffee machines by retrofitting the conventional machines with an adapter. 
     In keeping with these objects, and with still others which will become apparent hereafter, one aspect of the invention resides in a coffee machine which, briefly stated, may comprise 
     a removable adapter; 
     connecting means for connecting the adapter to the distributor of the machine so as to receive hot water from the distributor; and a box removably connectable to the adapter and defining therewith an extraction chamber in which a prefabricated water-permeable coffee pod may be installed prior to connection of the box to the adapter. 
     The invention will hereafter be described with reference to an exemplary embodiment as illustrated in the appended drawings. It is to be understood, however, that this embodiment is shown only to illustrate the invention and is not to be considered limiting of the scope or possible modifications of the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a vertical cross-section of an adapter embodying the invention, installed in a retrofitted conventional coffee machine; and 
     FIG. 2 is a view analogous to FIG. 1 but showing the adapter, a box for the same and a coffee pod in the extraction chamber. 
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
     FIGS. 1 and 2 fragmentarily (broken lines) illustrate a conventional coffee-brewing machine 2 and an adapter 1 for retrofitting it with the present invention. The adapter 1 is applied to the hot water distributor of the machine 2 and water leakage between them is prevented by a seal 30 (e.g. O-ring seal of rubber or synthetic plastic material). Adapter 1 has ribs or wings 3, 4 which are inserted into slots or grooves 3&#39;, 4&#39; of the machine 2 (these slots are present in any case so as to hold the conventional coffee container which is removed when adapter 1 is to be installed) in order to connect the two together. For ease of handling the adapter 1 may be provided with a handle 5. 
     The adapter is provided with a passage 7 which, when the adapter is installed on the machine 2, has a vertical orientation. The machine 2 itself, or rather its hot water distributor, is provided with a vertical passage 6 with which the passage 7 is aligned and in communication. The lower end portion of passage 7 is enlarged so as to form a cylindrical chamber 8 the inner wall of which contains part of a screw thread 8a adapted to threadably receive a diffuser 9 which is screwed into this thread 8a. The bottom of diffuser 9 is spaced from the cylindrical wall of chamber 8 to define with this wall a space 10. In the region of this space 10 the diffuser 9 is closed by a transverse wall 9a. Openings 11 are provided in diffuser 9 to permit water to flow outwardly from the diffuser 9. Underneath this wall 9a the adapter 1 includes at its lower end a flat chamber 12 of circular cross-section which is concentric to chamber 8 and communicates therewith via the space 10. A circular seal (e.g. O-ring) 13 of rubber or synthetic plastic material is partially received in a similarly circular recess 14 of the adapter 1, surrounding the chamber 12. Extensions 15, 16 of the adapter are provided with slots 17, 18 which serve for applying a box 19 to the adapter. 
     FIG. 2 shows the box 19 which has ribs or wings 20, 21 which are receivable in the slots 17, 18 in order to releasably connect the box to the adapter 1. Box 19 also has a depression or recess in which a filter 22 is received and which defines with the bottom surface of the recess a chamber 23. A prefabricated (i.e. commercially available) coffee pod 24 is received in the extraction chamber 23a defined within the chamber 12 by the filter 22. The pod 24 has a circular peripheral edge portion constituted by the overlapped and connected edges of two overlying layers of water-permeable filter paper; edge portion 24a is water-tightly clamped between seal 13 and the flat upper surface of box 19. A hollow extension 25 of box 19 projects downwardly therefrom and includes a sealing ring 26 (e.g. O-ring) of rubber or synthetic plastic material, about which a nozzle 27 is engaged in such a manner that passages 28 and 29 of the nozzle 27 and of the extension 25, respectively, are coaxial and in communication with one another and with chamber 23. For ease of manipulation the box 19 may be provided with a handle 31. 
     In the operation of a coffee machine retrofitted with the inventive structure as described above, an operator applies to adapter 1 under the hot water distributor of the machine 2, places a pod 24 over the filter 22 in box 19 and applies the box to the adapter 1. The operator then operates the machine in the normal manner, so that hot water is delivered which passes from passage 6 into passage 7 and diffuser 9, flows out through openings 11, spreads through chamber 12 and penetrates through pod 24. Coffee is thus brewed which passes through the filter 22 and runs off through the outlet passages 28 and 29. 
     By resorting to the invention a conventional coffee machine, e.g. an espresso machine, can be either permanently retrofitted to operate with the advantageous prefabricated coffee pods, or it can even be selectively operated in two modes; i.e. by using either loose ground coffee or, at the option of an operator, using coffee pods. Furthermore, the invention makes it possible to offer single-serving coffee products of a particular nature. For example, it is a simple matter to brew a cup of caffeine-free coffee, using the adapter 1, if the operator has a pod 24 of such coffee on hand. 
     While the invention has hereinbefore been described with reference to a specific exemplary embodiment, it is not, however, intended to thereby limit the invention to the illustrated embodiment and any and all changes and modifications that may offer themselves are intended to be encompassed within the scope of the appended claims.