Coffee brewing press with displaceable agitator

Abstract

A beverage brewing press has an open topped container for receiving a liquid and particulate matter to be brewed into a beverage, a hollow plunger shaft, a sealing filter piston disposed on the plunger shaft, the sealing filter piston having a peripheral seal slidably sealing to an interior of the container and for separating the interior of the container into a first compartment and a second compartment, the piston having a filter thereon for allowing brewed beverage to be filtered from the first compartment into the second compartment upon displacement of the piston, an agitator disposed below the piston, the agitator being fastened to an agitator shaft disposed concentrically rotatably and slidably in the hollow plunger shaft, a displaceable distance being provided between the agitator and the piston, the agitator shaft being slidable in the plunger shaft to take-up the displaceable distance between the agitator and the piston when the piston moves toward the agitator due to an axial force exerted on the plunger shaft moving the piston in the direction of the agitator. In some embodiments, a spring is provided to absorb the displaceable distance and may also transmit rotational force to the agitator.

What is claimed is: 
     
         1 . A beverage brewing press comprising:
 an open topped container for receiving a liquid and particulate matter to be brewed into a beverage;   a plunger shaft having a proximal end and a distal end;   a sealing filter piston assembly received slidably in the open topped container and disposed at the distal end of the plunger shaft, the sealing filter piston assembly having a peripheral seal for sealing slidably to an interior wall of the container and for separating the interior of the container into a first compartment and a second compartment, the sealing filter piston assembly having a filter thereon for allowing brewed beverage to be filtered and passed from the first compartment of the container into the second compartment of the container upon displacement of the sealing filter piston assembly in the container;   an agitator blade assembly disposed below the sealing filter piston assembly in the first compartment, the agitator blade assembly being fastened to a distal end of an agitator shaft having a proximal and distal end;   the plunger shaft comprising a hollow shaft, the agitator shaft being disposed concentrically rotatably and slidably in the plunger shaft, the agitator shaft allowing rotatable movement to be transmitted to the agitator blade assembly;   the agitator blade assembly being disposed such that there is a displaceable distance between the agitator blade assembly and the sealing filter piston assembly; and   the agitator shaft being slidable in the plunger shaft when the sealing filter piston assembly and agitator blade assembly displace toward each other due to a force being exerted on the plunger shaft moving the sealing filter piston assembly in the direction of the agitator blade assembly toward the bottom of the container.   
     
     
         2 . The beverage brewing press of  claim 1 , further comprising a knob for providing a rotational force to the agitator shaft to rotate the agitator blade assembly. 
     
     
         3 . The beverage brewing press of  claim 2 , further comprising a further knob disposed at the proximal end of the hollow plunger shaft for providing an axial force on the plunger shaft to displace the sealing filter piston assembly in the container. 
     
     
         4 . The beverage brewing press of  claim 2 , further comprising a spring in communication with the agitator shaft for absorbing at least a part of the displaceable distance between the agitator blade assembly and the sealing filter piston assembly when the sealing filter piston assembly and agitator blade assembly displace toward each other. 
     
     
         5 . The beverage brewing press of  claim 4 , wherein the agitator shaft is a one piece shaft having a stepped-down diameter portion with the spring being disposed concentrically around the stepped-down diameter portion between a shoulder formed on the agitator shaft where the agitator shaft steps-down to the stepped-down diameter portion and an end of the plunger shaft. 
     
     
         6 . The beverage brewing press of  claim 5 , wherein a further knob is provided at the proximal end of the hollow plunger shaft for providing an axial force on the plunger shaft to displace the sealing filter piston assembly in the container and the further knob is disposed concentrically about the agitator shaft allowing the agitator shaft to rotate freely in the further knob, and wherein the spring is captured between the shoulder of the agitator shaft and the further knob. 
     
     
         7 . The beverage brewing press of  claim 1 , wherein the agitator shaft is a two piece shaft comprising a first diameter first shaft and a reduced diameter second shaft that is slidable in the first shaft and keyed to the first shaft to allow transmission of a rotatable force between the first and second shafts, the shafts being slidable to take-up at least in part the displaceable distance between the agitator blade assembly and the sealing filter piston assembly. 
     
     
         8 . The beverage brewing press of  claim 7 , further comprising a spring in communication with the agitator shaft for absorbing at least a part of the displaceable distance between the agitator blade assembly and the sealing filter piston assembly when the sealing filter piston assembly and agitator blade assembly displace toward each other. 
     
     
         9 . The beverage brewing press of  claim 8 , wherein the spring is concentrically disposed about the reduced diameter second shaft between an end of the first shaft forming a shoulder for abutting against one end of the spring and an end of the hollow plunger shaft. 
     
     
         10 . The beverage brewing press of  claim 9 , wherein the first shaft has a keyway slidably receiving a key on the second shaft. 
     
     
         11 . The beverage brewing press of  claim 10 , wherein the keyway has a dogleg to a main portion of the keyway to allow capturing the key in the main portion of the keyway to prevent disconnection of the first and second shafts and furthermore allowing disconnection of the first and second shafts when the key is oriented in the dogleg. 
     
     
         12 . The beverage brewing press of  claim 11 , further comprising a catch in the main portion of the keyway for catching the key in the keyway through bias provided by the spring and for preventing entry of the key into the dogleg to prevent disconnection of the first and second shafts. 
     
     
         13 . The beverage brewing press of  claim 9 , further comprising a collar at the proximal end of the hollow plunger shaft for abutting against the spring. 
     
     
         14 . The beverage brewing press of  claim 9 , further comprising a knob on the second shaft for providing a rotational force to the agitator shaft to rotate the agitator blade assembly. 
     
     
         15 . The beverage brewing press of  claim 2 , wherein the knob is threaded to the agitator shaft to allow the agitator shaft and agitator blade assembly to be removed from the hollow plunger shaft. 
     
     
         16 . The beverage brewing press of  claim 4 , wherein the spring transmits the rotational force from the knob to the agitator shaft to rotate the agitator blade assembly. 
     
     
         17 . The beverage brewing press of  claim 1 , wherein the sealing filter piston assembly is clamped between a collar attached to the hollow plunger shaft and a threaded nut affixed to the sealing filter piston assembly to fix the sealing filter piston assembly on the plunger shaft and to allow disassembly of the sealing filter piston assembly and disassembly from the plunger shaft. 
     
     
         18 . The beverage brewing press of  claim 1 , further comprising a removeable cover received on the open top having an opening therein for slidably receiving the plunger shaft. 
     
     
         19 . A beverage brewing press comprising:
 an open topped container for receiving a liquid and particulate matter to be brewed into a beverage;   a removable cover received on the open top having an opening therein for slidably receiving a plunger shaft having a proximal and a distal end;   a sealing filter piston assembly disposed at the distal end of the plunger shaft, the sealing filter piston assembly having a peripheral seal for sealing slidably to an interior wall of the container and for separating the interior of the container into a first compartment and a second compartment, the sealing filter piston assembly having a filter thereon for allowing brewed beverage to be filtered and passed from the first compartment of the container into the second compartment of the container upon displacement of the sealing filter piston assembly in the container;   an agitator blade assembly disposed below the sealing filter piston assembly in the first compartment, the agitator blade assembly being fastened to a distal end of an agitator shaft having a proximal and distal end;   the plunger shaft comprising a hollow shaft, the agitator shaft being disposed concentrically rotatably and slidably in the plunger shaft, the agitator shaft allowing rotatable movement to be transmitted to the agitator blade assembly;   the agitator blade assembly being disposed such that there is a displaceable distance between the agitator blade assembly and the sealing filter piston assembly;   a spring disposed in communication with the agitator shaft for exerting an axial force on the agitator shaft;   the agitator shaft comprising a one piece shaft having a stepped-down diameter portion with the spring being disposed concentrically around the stepped-down diameter portion between a shoulder formed on the agitator shaft where the agitator shaft steps-down to the stepped-down diameter portion and an end of the plunger shaft;   the spring absorbing at least a part of the displaceable distance between the agitator blade assembly and the sealing filter piston assembly when the sealing filter piston assembly and agitator blade assembly displace toward each other due to an axial force being exerted on the plunger shaft to move the sealing filter piston assembly in the direction of the agitator blade assembly toward the bottom of the container;   wherein a knob is provided at the proximal end of the agitator shaft for providing a rotational force to the agitator shaft to rotate the agitator blade assembly; and   further comprising a second knob disposed at the proximal end of the hollow plunger shaft for providing the axial force on the plunger shaft to displace the sealing filter piston assembly in the container.   
     
     
         20 . A beverage brewing press comprising:
 an open topped container for receiving a liquid and particulate matter to be brewed into a beverage;   a removable cover received on the open top having an opening therein for slidably receiving a plunger shaft having a proximal end and a distal end;   a sealing filter piston assembly disposed at the distal end of the plunger shaft, the sealing filter piston assembly having a peripheral seal for sealing slidably to an interior wall of the container and for separating the interior of the container into a first compartment and a second compartment, the sealing filter piston assembly having a filter thereon for allowing brewed beverage to be filtered and passed from the first compartment of the container into the second compartment of the container upon displacement of the sealing filter piston assembly in the container;   an agitator blade assembly disposed below the sealing filter piston assembly in the first compartment, the agitator blade assembly being fastened to an agitator shaft, the agitator shaft allowing rotatable movement to be transmitted to the agitator blade asssembly;   the plunger shaft comprising a hollow shaft, the agitator shaft being disposed concentrically rotatably and slidably in the plunger shaft, the agitator shaft allowing rotatable movement to be transmitted to the agitator blade assembly;   the agitator blade assembly being disposed such that there is a displaceable distance between the agitator blade assembly and the sealing filter piston assembly;   a spring disposed in communication with the agitator shaft for exerting a force on the agitator shaft;   the agitator shaft comprising a two piece shaft comprising a first diameter first shaft and a reduced diameter second shaft that is slidable in the first shaft and keyed to the first shaft to allow transmission of a rotatable force between the first and second shafts;   the spring absorbing at least a part of the displaceable distance between the agitator blade assembly and the sealing filter piston assembly when the sealing filter piston assembly and agitator blade assembly displace toward each other due to an axial force being exerted on the plunger shaft moving the sealing filter piston assembly in the direction of the agitator blade assembly toward the bottom of the container;   wherein the spring is concentrically disposed about the reduced diameter second shaft between an end of the first shaft forming a shoulder for abutting against one end of the spring and an end of the hollow plunger shaft; and   further comprising a knob on the second shaft for providing a rotational force to the agitator shaft to rotate the agitator blade assembly.   
     
     
         21 . The beverage brewing press of  claim 20 , wherein the knob also allows the axial force to be exerted on the plunger shaft. 
     
     
         22 . A beverage brewing press comprising:
 an open topped container for receiving a liquid and particulate matter to be brewed into a beverage;   a plunger shaft having a proximal end and a distal end;   a sealing filter piston assembly received slidably in the open topped container and disposed at the distal end of the plunger shaft, the sealing filter piston assembly having a peripheral seal for sealing slidably to an interior wall of the container and for separating the interior of the container into a first compartment and a second compartment, the sealing filter piston assembly having a filter thereon for allowing brewed beverage to be filtered and passed from the first compartment of the container into the second compartment of the container upon displacement of the sealing filter piston assembly in the container;   an agitator blade assembly disposed below the sealing filter piston assembly in the first compartment, the agitator blade assembly being fastened to a distal end of an agitator shaft having a proximal and distal end;   the plunger shaft comprising a hollow shaft, the agitator shaft being disposed concentrically rotatably and slidably in the plunger shaft, the agitator shaft allowing rotatable movement to be transmitted to the agitator blade assembly;   the agitator blade assembly being disposed such that there is a displaceable distance between the agitator blade assembly and the sealing filter piston assembly; and   the agitator shaft being slidable in the plunger shaft when the sealing filter piston assembly and agitator blade assembly displace toward each other due to a force being exerted on the plunger shaft moving the sealing filter piston assembly in the direction of the agitator blade assembly toward the bottom of the container;   further comprising a spring in communication with the agitator shaft for absorbing at least a part of the displaceable distance between the agitator blade assembly and the sealing filter piston assembly when the sealing filter piston assembly and agitator blade assembly displace toward each other;   further wherein the spring is fastened to the agitator shaft for transmitting a rotational force to the agitator shaft to rotate the agitator blade assembly.   
     
     
         23 . The beverage brewing press of  claim 22 , wherein the spring is attached for rotational movement between a knob and the agitator shaft.