Beverage maker, and pump unit and cartridge for use in a beverage maker

Abstract

A pump unit includes a reservoir for containing a liquid, a duct system for conveying the liquid, and a pumping section for subjecting the liquid to a pumping force. The initial filling of at least a portion of a duct for conveying the liquid from the reservoir to the pumping section is brought about under the influence of another force other than the pumping force, for example, under the influence of gravity.

1 . A pump unit for use in a beverage maker comprising:
 a reservoir for containing a fluid;   a duct system having at least one duct which is connected to the reservoir, and which is adapted to conveying the fluid under the influence of a pumping force; wherein the pump unit is adapted to allowing for an initial filling of a portion of the duct with the fluid based on a further force other than the pumping force.   
     
     
         2 . The pump unit according to  claim 1 , further comprising a pumping section where the fluid is subjected to the pumping force during operation of the pump unit, wherein the at least a portion of the duct extends between the reservoir and the pumping section, and wherein the pump unit is adapted to allowing for the initial filling of this portion of the duct with the fluid based on the further force. 
     
     
         3 . The pump unit according to  claim 1 , which is adapted to allowing for the initial filling of at least a portion of the duct with the fluid based on a capillary force. 
     
     
         4 . The pump unit according to  claim 3 , wherein the duct is locally restricted. 
     
     
         5 . The pump unit according to  claim 4 , wherein, at a length along which the duct is locally restricted, the duct comprises at least two subducts. 
     
     
         6 . The pump unit according to  claim 3 , wherein material of the duct is a material with which the fluid has a better wetting than wetting of surrounding material. 
     
     
         7 . The pump unit according to  claim 3 , comprising means which are adapted to ensuring wetting of the fluid with the duct. 
     
     
         8 . The pump unit according to  claim 7 , wherein the means which are adapted to ensuring wetting of the fluid with the duct comprise a layer of a material that is applied to an inner surface of the duct and that has a better wetting with the fluid than wetting of surrounding material. 
     
     
         9 . The pump unit according to  claim 7 , wherein the means which are adapted to ensuring wetting of the fluid with the duct comprise means for causing an electro-wetting effect between the fluid and the duct by applying a voltage. 
     
     
         10 . The pump unit according to  claim 1 , wherein configuration of the reservoir and the duct allows for the initial filling of the portion of the duct with the fluid based on gravity. 
     
     
         11 . The pump unit according to  claim 10 , wherein at least an upper portion of the reservoir is positioned at a higher level than at least a portion of the duct. 
     
     
         12 . The pump unit according to  claim 1 , adapted to preventing leaking away of fluid from the duct system after the initial filling has taken place. 
     
     
         13 . The pump unit according to  claim 12 , wherein a level of an outlet of the duct system is higher than a maximum level of fluid in the reservoir. 
     
     
         14 . The pump unit according to  claim 12 , further comprising a substrate in which the duct system is arranged, wherein a portion of the substrate surrounding an outlet of the duct system comprises a material with which the fluid has poorer wetting than wetting of surrounding material. 
     
     
         15 . The pump unit according to  claim 12 , comprising a substrate in which the duct system is arranged, wherein a portion of the substrate surrounding an outlet of the duct system is covered by a layer of a material that has poorer wetting with the fluid than wetting of surrounding material. 
     
     
         16 . The pump unit according to  claim 15 , wherein the layer of the material that has the poorer wetting with the fluid is part of a removable seal for sealing the outlet of the duct system. 
     
     
         17 . The pump unit according to  claim 12 , wherein a ring-shaped portion of an inner surface of at least one of the ducts of the duct system is covered by a layer of a material that has poorer wetting with the fluid than wetting of surrounding material. 
     
     
         18 . The pump unit according to  claim 12 , comprising an obstruction), which is adapted to remain in place when the further force is exerted during the initial filling, and which is adapted to being removed under influence of the pumping force. 
     
     
         19 . The pump unit according to  claim 18 , further comprising a valve door which is pivotably arranged inside the duct system. 
     
     
         20 . The pump unit according to  claim 12 , further comprising an obstruction which is adapted to dissolving when its temperature exceeds a threshold which is above a temperature of the fluid that is supplied during the initial filling. 
     
     
         21 . The pump unit according to  claim 1 , wherein the duct system comprises at least two ducts for conveying the fluid, which are joined at a certain position in the pump unit. 
     
     
         22 . The pump unit according to  claim 21 , wherein the reservoir is adapted to containing a liquid, wherein the duct that is connected to the reservoir is adapted to conveying the liquid, and wherein another duct is adapted to conveying steam. 
     
     
         23 . A pump unit for use in a beverage maker, comprising a pump and a duct system having at least one duct for conveying a fluid under the influence of a pumping force provided by the pump; wherein the pump unit is adapted to preventing leaking away of fluid from the duct system. 
     
     
         24 . The pump unit according to  claim 23 , further comprising a reservoir for containing the fluid, wherein a level of an outlet of the duct system is higher than a maximum level of fluid in the reservoir. 
     
     
         25 . The pump unit according to  claim 23 , further comprising a substrate in which the duct system is arranged, wherein a portion of the substrate surrounding an outlet of the duct system comprises a material with which the fluid has poorer wetting than wetting of surrounding material. 
     
     
         26 . The pump unit according to  claim 23 , comprising a substrate in which the duct system is arranged, wherein a portion of the substrate surrounding an outlet of the duct system is covered by a layer of a material that has poorer wetting with the fluid than wetting of surrounding material. 
     
     
         27 . The pump unit according to  claim 26 , wherein the layer of the material that has the poorer wetting with the fluid is part of a removable seal for sealing the outlet of the duct system. 
     
     
         28 . The pump unit according to  claim 23 , wherein a ring-shaped portion of an inner surface of at least one of the ducts of the duct system is covered by a layer of a material that has poorer wetting with the fluid than wetting of surrounding material. 
     
     
         29 . The pump unit according to  claim 23 , comprising an obstruction, which is adapted to being removed under influence of the pumping force. 
     
     
         30 . The pump unit according to  claim 29 , comprising a valve door which is pivotably arranged inside the duct system. 
     
     
         31 . The pump unit according to  claim 23 , further comprising an obstruction which is adapted to dissolving when its temperature exceeds a threshold that is above ambient temperature. 
     
     
         32 . A cartridge for use in a beverage maker, comprising at least the duct system of the pump unit according to  claim 1 . 
     
     
         33 . The cartridge according to  claim 32 , which is adapted to being used as a disposable. 
     
     
         34 . A beverage maker, comprising a pump unit according to  claim 1 , wherein the pump unit is an integral part of the beverage maker. 
     
     
         35 . A beverage maker, comprising a space for receiving a cartridge according to  claim 32 .