Coffee maker for brewing coffee powder contained in a cartridge

Abstract

The coffee maker for brewing powder coffee contained in a cartridge comprises a brewing chamber adapted to receive the cartridge, at least one punching member for punching the cartridge and a pump for feeding brewing water into the brewing chamber. In order to avoid that the prepared coffee shows froth at its surface, the coffee maker comprises means for restricting the amount of water fed by the pump into the brewing chamber per unit of time. This means ensures that the brewing water flows through the cartridge essentially unpressurized.

1 . A coffee maker for brewing coffee powder contained in a cartridge, comprising:
 a brewing chamber adapted to receive said coffee powder cartridge;   a controllable pump for controllably feeding brewing water through a conduit into said brewing chamber;   a heater for heating the brewing water in said conduit; and   means for restricting an amount of the heated brewing water fed into said brewing chamber per unit of time to control the heated brewing water flow through said powder coffee cartridge, wherein the means for restricting the amount of heated brewing water is inserted into said conduit.   
     
     
         2 . The coffee maker according to  claim 1 , wherein said means for restricting the amount of the heated brewing water restrict the amount of brewing water fed into said brewing chamber per unit of time to not more than 12 liters per hour. 
     
     
         3 . The coffee maker according to  claim 1 , wherein at least two punching members are provided for punching a bottom of the cartridge as well as a cover of the cartridge, whereby means are provided for punching said bottom and said cover of said cartridge by said punching members before heated brewing water is fed to the cartridge by means of said pump. 
     
     
         4 . The coffee maker according to  claim 1 , wherein said brewing chamber comprises a cartridge retainer and a closing plate member, both said cartridge retainer and said closing plate member being provided each with a punching member, said coffee maker further comprising means for moving said cartridge container and said closing plate member relative to each other from an open condition of said brewing chamber to a closed condition thereof, whereby said cartridge contained in said brewing chamber is punched at its cover and its bottom by means of said punching members upon closing said brewing chamber. 
     
     
         5 . The coffee maker according to  claim 4 , wherein said closing plate member and said cartridge retainer both are provided with a centrally located punching member. 
     
     
         6 . The coffee maker according to  claim 4 , wherein said closing plate member or said cartridge retainer is provided with a centrally located punching member. 
     
     
         7 . The coffee maker according to  claim 1 , wherein said means for restricting the amount of brewing water fed into said brewing chamber per unit of time comprises means for restricting the flow rate of said pump. 
     
     
         8 . The coffee maker according to  claim 7 , wherein said controllable pump is operated with alternating current, and in which said means for restricting the flow rate of said controllable pump comprises a phase controlled modulator, a wave packet controller or a controller for changing the frequency. 
     
     
         9 . The coffee maker according to  claim 1 , wherein said means for restricting the amount of brewing water fed into said brewing chamber per unit of time comprises an adjustable throttle valve inserted into said conduit for varying an effective cross sectional flow area of said conduit. 
     
     
         10 . The coffee maker according to  claim 9  comprising:
 a manually operated selector switch; and 
 a control unit operationally connected to said switch and at least one of said pump and said throttle valve for restricting the amount of heated brewing water fed to said brewing chamber per unit of time. 
 
     
     
         11 . The coffee maker according to  claim 4 , wherein said closing plate member is adapted to press said cartridge along an annular seating area against the end face of said cartridge retainer upon closing said brewing chamber. 
     
     
         12 . The coffee maker according to  claim 1 , further comprising at least one sensor for decoding a label or marking provided on said cartridge, whereby said sensor is operationally connected to said control unit for restricting the amount of heated brewing water fed onto said brewing chamber per unit of time in response to the information content of said label or marking. 
     
     
         13 . A coffee powder cartridge adapted to be used in a coffee maker according to  claim 1 , the bottom of said cartridge comprising an aperture covered by a foil fixed to the inner side of said bottom. 
     
     
         14 . The coffee powder cartridge according to  claim 13 , the cartridge comprising a cup shaped lower portion, the bottom thereof constituting the cartridge bottom, whereby the foil covering the aperture provided in the cartridge bottom is made of a material that has a lower ductility and a lower tensile strength than the material of the cup shaped lower portion to ensure that the foil reliably tears open under the influence of a punching member upon closing the brewing chamber. 
     
     
         15 . A coffee maker for brewing coffee powder contained in a cartridge, comprising:
 a brewing chamber adapted to receive said coffee powder cartridge;   a controllable pump configured to controllably feed brewing water through a conduit into said brewing chamber;   a heater arranged to heat the brewing water in said conduit; and   an adjustable throttle valve inserted into said conduit to restrict an amount of the heated brewing water fed into said brewing chamber per unit of time to control the heated brewing water flow through said powder coffee cartridge.   
     
     
         16 . The coffee maker according to  claim 15 , wherein said adjustable throttle valve restricts the amount of brewing water fed into said brewing chamber per unit of time to not more than 12 liters per hour. 
     
     
         17 . The coffee maker according to  claim 15 , wherein at least two punching members are provided and arranged to punch a bottom of the cartridge as well as a cover of the cartridge before heated brewing water is fed to the cartridge by said pump. 
     
     
         18 . The coffee maker according to  claim 15 , wherein said brewing chamber comprises a cartridge retainer and a closing plate member, both said cartridge retainer and said closing plate member being provided each with a punching member, said coffee maker further comprising a retainer arranged to move said cartridge container and said closing plate member relative to each other from an open condition of said brewing chamber to a closed condition thereof, whereby said cartridge contained in said brewing chamber is punched at its cover and its bottom by means of said punching members upon closing said brewing chamber. 
     
     
         19 . The coffee maker according to  claim 18 , wherein said closing plate member and said cartridge retainer both are provided with a centrally located punching member. 
     
     
         20 . The coffee maker according to  claim 18 , wherein said closing plate member or said cartridge retainer is provided with a centrally located punching member. 
     
     
         21 . The coffee maker according to  claim 18 , wherein said closing plate member is adapted to press said cartridge along an annular seating area against the end face of said cartridge retainer upon closing said brewing chamber. 
     
     
         22 . The coffee maker according to  claim 15 , comprising a control unit operationally connected to at least one of said pump and said throttle valve. 
     
     
         23 . The coffee maker according to  claim 22 , wherein said controllable pump is operated with alternating current, and in which said control unit comprises a phase controlled modulator, a wave packet controller or a controller for changing the frequency. 
     
     
         24 . The coffee maker according to  claim 22 , comprising a switch connected to said control unit and operable to control said control unit into a first state to direct pressurized heated brewing water into said brewing chamber sufficient for preparing an espresso beverage and into a second state to direct essentially unpressurized water into said brewing chamber sufficient for preparing a frothless beverage. 
     
     
         25 . The coffee maker according to  claim 22 , further comprising at least one sensor for decoding a label or marking provided on said cartridge, whereby said sensor is operably connected to said control unit for restricting the amount of heated brewing water fed onto said brewing chamber per unit of time in response to the information content of said label or marking. 
     
     
         26 . A coffee powder cartridge adapted to be used in a coffee maker according to  claim 15 , the bottom of said cartridge comprising an aperture covered by a foil fixed to the inner side of said bottom. 
     
     
         27 . The coffee powder cartridge according to  claim 26 , said cartridge comprising a cup shaped lower portion, the bottom thereof constituting the cartridge bottom, whereby the foil covering the aperture provided in the cartridge bottom is made of a material that has a lower ductility and a lower tensile strength than the material of the cup shaped lower portion to ensure that the foil reliably tears open under the influence of a punching member upon closing the brewing chamber.