Abstract:
A delivery head for a beverage preparation machine comprising: an upwardly directed inlet for supplying water to a cartridge received in the delivery head; a downwardly directed outlet for outflow of beverage; a barcode reader having a barcode reader window through which signals may be transmitted; wherein the inlet, the outlet and the barcode reader window are arranged in a line with the outlet being intermediate the inlet and the barcode reader window.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a U.S. national phase application filed under 35 U.S.C. §371 of International Application PCT/US2008/063818, filed on May 16, 2008, designating the United States, which claims benefit to U.S. Application No. 60/940,118, filed on May 25, 2007, and Great Britain application GB 0709590.4, filed on May 18, 2007, all of which are hereby incorporated by reference herein. 
    
    
     FIELD 
     The present invention relates to improvements in beverage preparation machines and beverage cartridges and in particular to a delivery head for a beverage preparation machine of the type which use pre-packaged containers of beverage ingredients and the pre-packaged containers used therein. 
     BACKGROUND 
     Beverage preparation machines such as coffee or tea brewing machines are well known. It is known to provide beverage preparation machines which dispense individual servings of beverage directly into a receptacle such as a cup. Such machines may derive the beverage from a bulk supply of beverage ingredients or from packages of beverage ingredients such as pods, pads or cartridges. An example of one type of such packages is shown in EP1440903. In the following specification such packages will be referenced by the general term cartridges. However, the invention is not limited to use with one particular type of pod, pad or cartridge. The beverages are formed from brewing, mixing, dissolving or suspending the beverage ingredients in water. For example, for coffee beverages, heated water is passed through the cartridges to form the extracted solution. The use of cartridges in such machines has become increasingly popular due to their convenience and the quality of the beverage produced. 
     For convenience it is known for such machines to include a mechanism for ejecting the cartridges from the delivery head of the machine after each dispense cycle. Also, for convenience it is known to provide such machines with a reader for detecting barcodes on cartridges in order to identify the type of cartridge or the required dispensing parameters prior to commencing the dispense cycle. However, combining an ejection mechanism with a reader for reading barcodes can cause problems associated with maintaining the cleanliness of the reader and thereby the consistency of operation of the reader. 
     SUMMARY 
     It is an object of the present invention to provide a delivery head and beverage preparation machine incorporating an improved ejection mechanism and barcode reader which help to address this problem. 
     Accordingly, the present invention provides a delivery head for a beverage preparation machine comprising: 
     an upwardly directed inlet for supplying water to a cartridge received in the delivery head; 
     a downwardly directed outlet for outflow of beverage; 
     a barcode reader having a barcode reader window through which signals may be transmitted; 
     wherein the inlet, the outlet and the barcode reader window are arranged in a line with the outlet being intermediate the inlet and the barcode reader window. 
     Preferably the delivery head comprises a first part defining a support surface for a cartridge, the inlet, the outlet, and the barcode reader window being located in or on the first part. 
     Preferably the support surface comprises a horizontal surface. 
     Preferably the inlet comprises an inlet piercer for forming an inlet opening in a cartridge received in the delivery head. 
     Preferably the outlet comprises an outlet piercer for forming an outlet opening in a cartridge received in the delivery head. 
     Preferably the inlet piercer and the outlet piercer are movable between an extended position and a retracted position. 
     Preferably the delivery head further comprises an ejection chute and the inlet, the outlet, the barcode reader window and the ejection chute are located in a line with the outlet and the inlet being intermediate the barcode reader window and the ejection chute. 
     Preferably the barcode reader window is located to a front of the delivery head and the ejection chute is located to a rear of the delivery head. 
     Preferably a centroid of the inlet, a centroid of the outlet and a centroid of the barcode reader window lie on a straight line. 
     The barcode reader window may comprise a rectangular window, wherein a longer edge of the rectangular window is arranged perpendicularly to a line joining the inlet, the outlet and the barcode reader window. 
     Preferably the delivery head further comprises a clamping member which is movable relative to a first part from an open position to a clamping position and to an ejection position; 
     in the open position the clamping member being positioned to enable loading of a cartridge into the delivery head; 
     in the clamping position the clamping member being clampable against said cartridge; 
     in the ejection position the clamping member being positioned to enable ejection of said cartridge; 
     the clamping member being movable in a direction substantially parallel to the first part from the clamping position to the ejection position wherein movement of the clamping member towards the ejection position is such that an inlet and an outlet of the cartridge are moved away from, and do not pass over, or in the vicinity of, the barcode reader window of the delivery head. 
     The present invention also provides a beverage preparation machine comprising a delivery head as described above. 
     Further, the present invention provides a beverage preparation system comprising a beverage preparation machine as described above and one or more cartridges, wherein the one or more cartridges contain one or more beverage ingredients. 
     The present invention also provides a cartridge for use in a beverage preparation machine of a type comprising: 
     a delivery head; 
     an upwardly directed inlet for supplying water to the cartridge received in the delivery head; 
     a downwardly directed outlet for outflow of beverage; and 
     a barcode reader having a barcode reader window through which signals may be transmitted; 
     the cartridge comprising, or being adapted to contain in use, a quantity of one or more beverage ingredients, 
     a lower surface of the cartridge comprising an inlet and an outlet arranged to communicate respectively with the inlet and outlet of the delivery head of the beverage preparation machine when the cartridge is inserted into the machine such that, in use, water from the inlet of the delivery head passes upwardly through the inlet of the cartridge and such that beverage produced from the water and the one or more beverage ingredients passes downwardly through the outlet of the cartridge to flow out of the outlet of the delivery head, 
     the lower surface of the cartridge further comprising a barcode which, in use, is readable by the barcode reader of the beverage preparation machine for controlling operation of the beverage preparation machine, 
     characterised in that the barcode, the inlet and the outlet of the cartridge are located in a line with the outlet being intermediate the inlet and the barcode. 
     Preferably the outlet is located at a centre or near a centre of the lower surface of the cartridge. 
     Preferably the inlet and the outlet of the cartridge are initially closed by one or more frangible membranes. 
     Preferably a centroid of the inlet, a centroid of the outlet and a centroid of the barcode lie on a straight line. 
     The barcode may comprise a rectangular arrangement of coding lines, wherein a longer edge of the rectangular arrangement is arranged perpendicularly to a line joining the inlet, the outlet and the barcode. 
     The present invention also provides a method of dispensing a beverage from a cartridge using a beverage preparation machine, 
     the beverage preparation machine being of the type having a delivery head comprising: an inlet for supplying water to the cartridge, an outlet for beverage, a barcode reader having a barcode reader window, an ejection chute, and a clamping member; the barcode reader window and the ejection chute being located in a line with the inlet and the outlet, and the inlet and the outlet being intermediate the barcode reader window and the ejection chute; 
     the cartridge being of the type comprising an inlet, an outlet and a barcode; the inlet, the outlet and the barcode being located in a line with the outlet intermediate the inlet and the barcode; 
     wherein the method comprises the steps of: 
     moving the clamping member into an open position; 
     inserting the cartridge into the delivery head; 
     moving the clamping member into a closed position such that the inlet, the outlet and the barcode of the cartridge are aligned respectively with the inlet, the outlet and the barcode reader window of the delivery head; 
     pumping water through the inlet of the delivery head and the inlet of the cartridge so as to form a beverage from the one or more beverage ingredients of the cartridge; 
     delivering said beverage out of the outlet of the insert and the outlet of the delivery head; 
     moving the clamping member from the closed position to the ejection position to move the cartridge into alignment with the ejection chute to achieve ejection of the cartridge from the delivery head; 
     wherein movement of the cartridge towards the ejection chute is such that the inlet and the outlet of the cartridge move away from, and do not pass over, or in the vicinity of, the barcode reader window of the delivery head. 
     Advantageously, with the barcode reader system and ejection system of the present invention the direction of movement of the cartridge on ejection is towards a rear of the delivery head away from the barcode window. This helps to prevent soiling of the barcode window by preventing the now open inlet and outlet of the cartridge passing over or in the vicinity of the window. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       An embodiment of the present invention will now be described, by way of example only, with reference to the accompanying drawings in which: 
         FIG. 1  is perspective view of a first version of beverage preparation machine according to the present invention which includes first and second delivery heads; 
         FIG. 2  is a perspective view of a second version of beverage preparation machine according to the present invention which includes a single delivery head; 
         FIG. 3  is a cross-sectioned perspective view of a delivery head according to the present invention in an open position; 
         FIG. 4  is a cross-sectioned perspective view of the delivery head of  FIG. 3  in the open position and with a first cartridge inserted; 
         FIG. 5  is a cross-sectioned perspective view of the delivery head of  FIG. 3  in a closed position with the cartridge in a dispensing position; 
         FIG. 6  is a cross-sectioned perspective view of the delivery head of  FIG. 3  in the closed position with a piercing unit of the delivery head in a raised position; 
         FIG. 7  is a cross-sectioned perspective view of the delivery head of  FIG. 3  in an ejection position; 
         FIGS. 8 a  and 8 b    are elevational views of the delivery head of  FIG. 3  with some parts shown in section and some parts omitted for clarity illustrating movement of a cartridge guide of the delivery head; 
         FIGS. 9 a  to 9 d    are cross-sectional views of the delivery head of  FIGS. 8 a  and 8 b    with some parts sectioned and with a second cartridge inserted, illustrating movement of the cartridge guide on closure of the delivery head; 
         FIG. 10  is a perspective view of a piercing mechanism of the delivery head of  FIG. 3 ; 
         FIGS. 11 a  and 11 b    illustrate operation of the piercing mechanism of  FIG. 10 ; 
         FIGS. 12 a  to 12 c    illustrate a piercer unit of the delivery head of  FIG. 3 ; and 
         FIG. 13  is a plan view of a beverage cartridge of the present invention comprising a barcode 
     
    
    
     DETAILED DESCRIPTION 
     The beverage preparation machines  1  of  FIGS. 1 and 2  each comprise a housing  2  containing the internal mechanisms of the machine such as a water reservoir, a pump, heating means and control means. 
     The machine  1  of  FIG. 2  comprises a single brewer. The machine  1  of  FIG. 1  comprises a first brewer and a second brewer coupled together. 
     Each brewer of the machines  1  comprises a delivery head  3  provided towards an upper part of the housing  2  in which, in use, is received a cartridge containing one or more beverage ingredients. The delivery head or heads  3  are connected with a chassis of the machine  1  on assembly. The delivery heads  3  are preferably identical. Beverage is dispensed from the brewer through an outlet spout  5  by pumping water from the reservoir of the brewer through the cartridge to form the beverage which is then directed through the outlet spout  5  into a cup  6 . As can be seen in  FIG. 1 , two outlet spouts  5  are provided for a machine with two brewers. 
     As shown in  FIG. 3 , the delivery head  3  comprises a lower part  80 , an upper mechanism  90  and a cartridge guide  110 . Some parts of the outer cowling of the delivery head have been omitted for clarity. In practice the outer cowling will comprise a number of mouldings shaped to contain and protect the internal components of the delivery head. 
     The lower part  80  comprises a housing  81  formed from upper and lower mouldings. The housing  81  defines a motor cavity  88  towards a rear of the delivery head  3 , a piercer unit cavity  86  towards a front of the delivery head  3  and a barcode reader cavity  87  at a foremost portion of the delivery head  3 . A forward part of the upper surface of the housing  81  is provided with a flattened support surface  82  in which is located a piercer unit aperture  83  and a barcode window  84 . Rearward of the support surface  82  the upper moulding is shaped to define an ejection chute  85  that is open to below the delivery head  3 . 
     The barcode window  84  is rectangular in shape to match the shape of a barcode applied or printed on the cartridges  70  to be used in the delivery head  3 . The barcode window  84  and piercer unit aperture  83  are arranged on a midline of the delivery head  3  with the longer edge of the barcode window  84  arranged perpendicularly to the midline of the delivery head  3 . As shown in  FIG. 13  the barcode  72  of cartridge  70  and the location of the inlet  72   a  and outlet  72   b  of the cartridge (which are both opened by the piercing mechanism) are likewise in a straight line. 
     The upper mechanism  90  comprises a carriage frame  95 , a handle  92 , a clamping mechanism  93 , a lead screw  96 , and a motor  97 . 
     The carriage frame  95  forms the core of the upper mechanism and provides a structural framework for the other components of the upper mechanism. The carriage frame  95  comprises an elongate frame extending from a front end  155  to a rear end  154  as shown in  FIG. 3 . The frame comprises two side members  151  and an upper member  152  joining the two side members  151 . The upper member  152  is provided with two upstanding webs  156  as most clearly shown in  FIG. 9 b   . Each side member  151  comprises an elongate side slot  106  and the upper member  152  comprises an elongate upper slot  153  as most clearly shown in  FIG. 5 . The carriage frame  95  is preferably formed from a single moulding and is symmetric about a midline of the delivery head  3 . 
     The carriage frame  95  is pivoted to the lower part  80  by a pair of hinges  98  formed on the upstanding webs  156  at pivot points  150  as most clearly seen in  FIGS. 9 b  to 9 d   . The hinges  98  are offset from the upper surface of the lower part  80  and positioned above the level of the support surface  82 . As most clearly shown in  FIG. 9 a    by omission of certain parts of the housing  91 , the hinges  98  may comprise a cog  157  having teeth  158  which engage with a damping member during pivoting of the carriage frame  95  to thereby provide control over the pivoting speed of the carriage frame  95 . For example, the damping member may act to ensure that if the handle  92  of the delivery head  3  is released when the carriage frame  95  is in the raised position then the carriage frame  95  pivots downwardly in a controlled manner rather than free-falling into contact with the lower part  80 . The damping member may comprise a cog suitable for engaging the cog  157  and a damper, such as a rotatable vane, movable within a viscous damping fluid such as oil. 
     The handle  92  is connected to the carriage frame  95  and extends around a front of the delivery head  3 . The handle  92  is pivotably connected to the carriage frame  95  by a mechanism such that with the carriage frame  95  in a lowered position the handle  92  can be depressed to engage hooks provided on the handle  92  with bosses provided on the lower part  80  in order to securely hold the carriage frame in the lowered position. An example of such a mechanism is described in EP1440644. However, such a mechanism is not relevant to the present invention. The clamping mechanism  93  comprises a cup-shaped clamp member  100  and a cup-shaped socket  94 . The clamp member  100  is provided with a central spigot  101 . A plurality of flexible protrusions  102  are provided on an exterior of the clamp member  101  which engage with an inwardly-directed flange  103  of the socket  94  so as to retain the clamp member  100  fixedly within the socket  94  on assembly. The socket  94  is provided on an upper surface with a cylindrical member  104  in which is seated a threaded nut  105 . The threaded nut  105  is engaged on the lead screw  96 . The socket  94  of the clamping mechanism  93  is also provided with a pair of bosses or similar which are engaged in, and slidable along the side slots  106  of the carriage frame  95  so as to maintain correct orientation of the socket  94  on operation of the lead screw  96 . Consequently, rotation of the lead screw  96  can be used to move the socket  94 , and hence the clamp member  100  reciprocally along the longitudinal axis of the upper mechanism  90  from the front end  155  to the rear end  154  of the carriage frame  95  as will be described below when the operation of the delivery head  3  is discussed. As best shown in  FIGS. 8 a  and 8 b    the socket  94  further comprises a pair of tail pieces  108  which extend rearwardly from either side of the cup-shaped body of the socket  94 . The tail pieces  108  are each provided with a pin  107  at or near a distal end thereof, the use of which will be described below. 
     The lead screw  96  is mounted to the carriage frame  95 . The lead screw  96  is located towards a top of the carriage frame  95  in the opening provided by the upper slot  153  as shown in  FIG. 5 . Thus, the lead screw  96  extends above the socket  94  and extends along the longitudinal axis of the upper mechanism  90  from the rear end  154  to the front end  155  of the carriage frame  95 . The motor  97  is operatively connected to a rear end of the lead screw  96  and is able to rotate the lead screw  96  both clockwise and counter-clockwise. As shown, the motor  97  is mounted to the carriage frame  95  and transverse the longitudinal axis of the upper mechanism  90  to save space and is connected to the lead screw  96  by means of a suitable gear arrangement such as bevel gears. 
     The cartridge guide  110  is located inbetween the lower part  80  and the upper mechanism  90 . The cartridge guide  110  rests on and is slidable relative to the lower part  80  whilst being operatively interconnected with the upper mechanism  90  as described below. 
     The cartridge guide  110  comprises an annular member  111  and two vertically extending webs  113 . The annular member  111  and webs  113  are formed as a single moulding from, for example, a plastics material. The annular member  111  comprises a ring defining an aperture  112  shaped to receive a cartridge  70 . The lower face of the cartridge guide  110  rests on the support surface  82 . Whilst the aperture  112  closely conforms to the shape of the cartridge  70  in order to enable precise orientation and placement of the cartridge, it is slightly larger than the cartridge  70  such that a cartridge  70  placed within the aperture  112  rests on the support surface  82  of the lower part  80  rather than on the cartridge guide  110  itself. The aperture  112  is shaped also to accommodate a handle portion  71  of the cartridge  70  as shown in  FIG. 4 . The handle  71  is thereby orientated to a front of the delivery head  3  and positioned symmetrically on the midline of the delivery head  3 . 
     The webs  113  are located on each side of the cartridge guide  110  and, as best shown in  FIGS. 8 a  and 8 b   , are each provided with a slot  114  of arcuate form in which, on assembly, the pins  107  of the socket  94  are slidingly received. Thus, the cartridge guide  110  and the clamping mechanism are interconnected. Each slot  114  comprises a first portion  115  in the shape of an arc having a centre of rotation coincident with the pivot point  150  of the clamping mechanism  93 . Each slot  114  also comprises a second portion  116  in the shape of an arc whose instantaneous centre of curvature is not co-incident with the pivot point  150 . The function of the slot  114  will be described below. 
     The delivery head  3  further comprises a barcode reader  120  and a piercing mechanism  119 . 
     The barcode reader  120  is located in the barcode reader cavity  87  and is orientated to be able to transmit and receive signals through the barcode window  84 . Due to the transverse orientation of the barcode window  84  and the barcode reader  120  it can be seen that the barcode reader  120  reads the barcodes of the cartridge  70  by sweeping a beam of light in a direction transversely across the delivery head. 
     The piercing mechanism  119  comprises a piercer unit  121 , a motor  130 , a lead screw  131  and a linkage mechanism  133 . The piercing mechanism  119  is operative to raise and lower the piercer unit  121 . The piercer unit  121  is located in the piercer unit cavity  86  of the lower part  80 . 
     As shown in  FIGS. 12 a  to 12 c    the piercer unit  121  comprises a body  122  having mounted therein an inlet piercer  123  and an outlet piercer  124 . The body  122  is provided with a conduit  125  linking the inlet piercer  123  with a fluid inlet  126  of the body  122 . The fluid inlet  126  is coupled by pipework to a supply of water on assembly of the delivery head with the remainder of the machine  1 . A seal member  128  is located on an upper face of the body  122  surrounding the inlet piercer  123  and the outlet piercer  124 . The seal member  128  is provided with raised annular portions  129  surrounding the piercing element of the inlet piercer  123  and the piercing element of the outlet piercer  124 . 
     The piercer unit cavity  86  is also provided with a spout chute  89  as shown in  FIG. 3  into which the piercer unit  121  extends. The spout chute  89  acts as a funnel to channel beverage discharged through the outlet piercer  124  to the outlet spout  5  located at a bottom of the spout chute  89 . 
     The motor  130  is located at a rear of the delivery head  3  remote from the piercer unit  121 . The motor  130  is orientated generally in line with a longitudinal axis of the lower part  80  but is angled downwardly slightly below the horizontal. The motor  130  is coupled to the lead screw  131  by means of a threaded, generally U-shaped, rear coupling member  138  as most clearly seen in  FIG. 10 . A distal end of the lead screw  131  is provided with an end stop. The motor  130  is able to rotate the lead screw  131  both clockwise and counter-clockwise in order to move the rear coupling member  138  reciprocally forwards and backwards relative to the lower part  80 . 
     As shown in  FIG. 10 , the linkage mechanism  133  comprises a U-shaped primary link  135  having a pair of forward-extending arms  135   a , a pair of secondary links  136 , a pair of tertiary links  137 , the rear coupling member  138  and a forward coupling member  149 . The linkage mechanism is mounted to the lower part  80  by means of a rear mounting plate  160 , a front mounting plate  161  and two side mounting plates  162  which are all securely mounted to an underside of the upper moulding of the lower part  80 . 
     A pair of first pivot points  139  are provided by the side mounting plates  162 . A pair of second pivot points  140  are provided by the front mounting plate  161 . 
     As most clearly shown in  FIGS. 10, 11   a  and  11   b , the U-shaped primary link  135  is rotatably coupled at a rear end to the rear coupling member  138 . 
     The forward coupling member  149  comprises a generally U-shaped member having two arms  146  and an interconnecting bridge  147 . The distal ends of the arms  146  are rotatably coupled to the first pivot points  139 . 
     The secondary links  136  are rotatably connected to the primary link arms  135   a  at third pivot points  141  such that a forward end of each primary link arm  135   a  is connected to a rear end of the respective secondary link  136 . The opposite end of each secondary link  136  is rotatably coupled to the forward coupling member  149  at fourth pivot points  148 . 
     The tertiary links  137  are connected between the third pivot points  141  (where the primary link arms  135   a  and secondary links  136  are coupled) and the second pivot points  140  on the front mounting plate  161 . 
     The piercing unit  121  is rigidly mounted to the interconnecting bridge  147  of forward coupling member  149  as shown in  FIG. 10  Alternatively the piercer unit  121  could be formed as one piece with the front coupling member  149 . 
     As most clearly shown in  FIG. 10 , the linkage mechanism  133  transfers motive force from the motor  130  at the rear of the delivery head  3  to a front of the delivery head  3 . In addition, by using pairs of primary link arms  135   a , secondary links  136  and tertiary links  137  as well as U-shaped members  135 ,  149  the linkage mechanism extends around the ejection chute  85  without impeding the chute as shown in  FIG. 5 . 
     Operation of the piercing mechanism  119  will be described below. 
     The beverage preparation machine also comprises a controller for controlling operation of the machine including operation of components of each delivery head  3  such as the motors  95 ,  130 , and the barcode reader  120 . 
     The delivery head  3  may also be provided with interlock or sensing devices linked to the controller to provide data to the controller on the position of the socket  94  on its lead screw  96 , the position of the piercing mechanism  119  and the position of the upper mechanism  90 , for example whether the upper mechanism  90  is in the closed position Typically an interlock is provided to confirm closure of the handle  92  when the upper mechanism  90  is in the lowered position. Operation of the delivery head  3  is prevented when this interlock indicates that the handle  92  is opened. 
     As an alternative to providing an interlock on the lead screw  96  to indicate the position of the socket  94  current sensing control may be used. In current sensing the current drawn by the motor  97  is monitored and the controller interprets an increase in the drawn current above a pre-set threshold to be indicative of the socket  94  having reached one of its end stops at either the front end  155  or rear end  154  of the carriage frame  95 . 
     In use, the delivery head  3  is first opened to allow insertion of a cartridge  70  of the type having a bowl-shaped upper portion  76  sealed by a flexible lower membrane  77  around a peripheral flange  78  by moving the upper mechanism  90  into the raised position as shown in  FIG. 3 . Opening of the upper mechanism is achieved by first opening the handle  92  to disengage the hooks from the bosses of the lower part  80  and then lifting the handle  92 . As shown in  FIG. 3  and in  FIG. 9 a   , in the raised position of the upper mechanism  90 , the cartridge guide  110  is positioned in a forward-most position to ease loading of the cartridge  70  and the clamping member  100  is raised as part of the upper mechanism  90 . The cartridge guide  110  is thus positioned because of the interaction of the pins  107  of the tail pieces  108  in the slots  114  of the cartridge guide  110 . In particular in the raised position each pin  107  is moved to a top of the first portion  115  of the slot  114  as shown in  FIG. 9   a.    
     The cartridge  70  is then inserted into the aperture  112  of the cartridge guide  110  such that the cartridge  70  rests on the support surface  82  as shown in  FIG. 4 . In  FIG. 4  the delivery head  3  is shown with a cartridge  70  having a relatively shallow profile. The handle portion  71  of the cartridge  70  is aligned towards a front of the delivery head  3  and lies on the midline of the delivery head  3 . 
     The upper mechanism  90  is then closed into the position shown in  FIG. 5  by pressing down on the handle  92 . Closure of the upper mechanism  90  causes the cartridge guide  110  and the cartridge  70  to slide rearwardly over the support surface  82  into a dispensing position wherein the cartridge  70  is correctly aligned with the piercer aperture  83  and the barcode window  84 . The rearward movement of the cartridge guide  110  is caused by the interaction of the pins  107  and slots  114 . As shown in  FIGS. 8 a , 8 b    and  FIGS. 9 a  to 9 d    downward rotation of the upper mechanism  90  causes the clamping mechanism  93  also to rotate downwardly moving the pins  107  first along the first portion  115  of the slots  114  and then along the second portion  116 . Movement of the pins  107  along the first portion  115  of the slots to the position shown in  FIG. 9 c    does not cause any movement of the cartridge guide  110  since the centre of curvature of the first portion  115  is coincident with the point of rotation of the clamping mechanism  93 . However, further downward rotation of the clamping mechanism  93  does cause rearward sliding of the cartridge guide  110  due to the pins  107  bearing against a rearmost face of the slots  114  to thereby force the cartridge guide  110  to move to accommodate the pin&#39;s movement into the position shown in  FIG. 9 d   . In the closed position of the clamping mechanism  93  the cartridge guide  110  has moved in a rearward direction by between 7.8 and 10 mm. 
     In the closed position the spigot  101  of the clamping member  100  is engaged in a relatively shallow central well  75  formed in the upper portion  76  of the cartridge  70 . The clamping member  100  is also provided with a formation  79  aligned with an inlet region of the cartridge  100 . The lower rim of the clamping member  100  is aligned with and is designed to make contact with the peripheral flange  78  of the cartridge  70  in the closed position. Thus, in the closed or clamped, position the clamping member  100  applies a clamping force on the cartridge  70 . This force is mainly applied to the central region of the cartridge  70  by the spigot  101  and to the inlet region of the cartridge  70  by the formation  79 . However, if required the lower rim of the clamping member  100  may apply a relatively small force to the peripheral flange  78 . At this point the piercer unit  121  is still lowered. Therefore the force applied to the cartridge  70  urges the cartridge into contact with the support surface  82 . Thus, the lower membrane  77  carries some of the applied load in the area immediately surrounding the piercer aperture  83 . In addition, the remainder of the load applied to the cartridge  70  is carried through the peripheral flange  78  where it contacts the support surface  82 . 
     Closure of the upper mechanism  90  also triggers operation of the barcode reader  120  to read the barcode on the cartridge  70  by transmitting through the barcode window  84 . The received detected signal is then fed to the controller which thereby determines the correct dispense parameters for the inserted cartridge, such as water temperature, volume, steeping time, etc. 
     Opening of the upper mechanism  90  after a dispense cycle and ejection have taken place results in a reversal of the movement of the cartridge guide  110  described above. 
     A particular advantage of this movement of the cartridge guide  110  is to allow accommodation of cartridges having a relatively deep profile, such as the type of cartridge  70  shown in  FIGS. 9 a  to 9 d   . As shown in  FIGS. 9 a  to 9 d    maintaining the cartridge guide  110  in the loading position of  FIG. 9 a    until the clamping mechanism  93  has rotated partially down to the point shown in  FIG. 9 c    allows the lower rim of the clamping member  100  to clear the upper rear point  73  of the cartridge  70 . The subsequent rearward movement of the cartridge  70  allows for a clamping member  100  that closely conforms to the diameter of the cartridge to be used whilst avoiding fouling of the clamping member&#39;s rim on a front face  74  of the cartridge or of the spigot  101  on the sides of the relatively deep central well  75  of the cartridge  70 . In this way the size of the clamping member  100  is minimised without requiring a substantially vertical movement of the clamping mechanism  93  to be used to allow insertion of cartridges of varying depth. 
     As shown in  FIG. 5 , at this point the piercer unit  121  is in the lowered position such that the inlet piercer  123  and outlet piercer  124  are fully below the level of the support surface  82 . On receipt of a start command from the user (by for example, pressing a start/stop button), the controller of the machine  1  operates the motor  130  to raise the piercing mechanism  119  into the raised position shown in  FIG. 6  such that the inlet piercer  123  and outlet piercer  124  are raised proud of the level of the support surface  82 . In the raised position the piercer unit  121  is raised to the point where the seal member  128  is orientated substantially horizontally with the general level of the seal member  128  being level with the support surface  82 . However, in this position the raised annular portions  129  of the seal member  128  lie slightly above the level of the support surface  82 . In this way the raised annular portions  129  are able to distort slightly and thereby tension the flexible lower membrane  77  of the cartridge  70 . The peripheral flange  78  of the cartridge  70  remains in contact with the support surface  82  due to the constraining contact of the lower rim of the clamping member  100 . 
     In addition, the upward movement of the piercer unit  121  urges the cartridge  70  more tightly against the spigot  101  and the formation  79  of the clamping member  100  to increase the clamping force which holds the cartridge  70  in position between the clamping member  100  and the piercer unit  121 . Thus, the combination of the action of the clamping member  100  and the piercer unit  121  creates a minimum clamping force of 30N at the inlet of the cartridge and a force of between 75 and 130N at the outlet. 
     The movement of the piercing mechanism  119  from lowered to raised position is most clearly seen in  FIGS. 11 a  and 11 b    and involves a rotation of the piercer unit  121  about its pivot point of between 5 and 10 degrees and preferably greater than 7.5 degrees. On operation of the motor  130 , the rear coupling member  138  is moved forwards by approximately 20 mm by rotation of the lead screw  131 . As a result of the coupling of the rear coupling member  138  with the primary link  135  the primary link  135  is moved substantially in a direction in line with the longitudinal axis of the primary link although this may be accompanied by a slight rotational movement of the primary link  135  relative to the rear coupling member  138 . At the same time the primary link arms  135   a  push on the lower ends of the secondary links  136 . Due to the constraint of the tertiary links  137 , which couple the primary link arms  135   a  and the secondary links  136  to the second pivot points  140 , the pushing movement of the primary link arms  135   a  causes the secondary links  136  to rotate in a clockwise sense as viewed in  FIG. 11 b   . This rotation results in upward rotation of the front coupling member  149  due to the coupling of the secondary links  136  to the front coupling member  149  and the coupling of the arms  148  of the front coupling member  149  to the first pivot points  139  of the side mounting plates  162 . Upward rotation of the front coupling member  149  consequently results in upward rotation of the piercer unit  121  due to the rigid connection of the piercer unit  121  to the front coupling member  149 . In the raised position, the tertiary links  137  are substantially vertical and also aligned with the secondary links  136  which are also vertically aligned. In this position the secondary and tertiary links are best able to resist the downward loads applied by the clamping member  100  to the cartridge  70 . The movement of the secondary and tertiary links also acts in the manner of a toggle clamp wherein the secondary and tertiary links snap into, and have a propensity to remain in, the position of  FIG. 11 b    until a positive retraction force is applied by the motor  130 . 
     Raising of the piercing mechanism  119  causes piercing of the cartridge  70  by the inlet piercer  123  and the outlet piercer  124  to form respectively an inlet and an outlet in the underside of the cartridge  70 . 
     Once the controller detects that the piercer unit  121  is in the raised position dispensation of a beverage from the cartridge  70  begins. As with operation of the lead screw  96  current sensing of the motor  130  may be used by the controller to determine the position of the piercer unit  121 . Heated water is channelled from the fluid inlet  126  through the conduit  125  and inlet piercer  123  and into the cartridge. The resultant beverage is discharged through the outlet piercer  124 , spout chute  89  and out of outlet  5  into a waiting receptacle  6 . 
     Once dispensation has stopped the piercer unit  121  is lowered by reversing the operation described above by operating the motor  130  in a reverse direction. This clears the inlet piercer  123  and the outlet piercer  124  out of the ejection path of the cartridge  70  and also removes a portion of the loading applied to the cartridge  70 . 
     The controller then operates motor  97  to eject the cartridge  70  by movement of the cartridge  70  to an ejection position. Operation of the motor  97  rotates the lead screw  96  causing the clamping socket  94  and clamping member  100  to slide rearwards into the position shown in  FIG. 7 . The clamping member  100  moves the cartridge  70  along with it thereby dragging the cartridge  70  over the ejection chute  85 . During this movement the cartridge  70  is still under some loading from the socket  94  of the upper mechanism  90 . Once the cartridge  70  is substantially or wholly aligned with the chute  85  it falls under gravity down the chute  85  into a waste bin in a lower part of the machine  1 . It is to be noted that during this movement the outer part of the housing  91  of the upper mechanism  90  remains stationary such that the motion of the clamping mechanism  93  remains internal to the delivery head  3 . A particular advantage is that the delivery head  3  does not need to be opened in order to eject the cartridge  70 . In addition, the clamping mechanism  93  affects not only clamping of the cartridge  70  during dispensation of beverage but also ejection of the cartridge  70 . 
     The motor  97  is then reversed to move the clamping mechanism  93  back into the forward position ready for the next dispensing cycle. 
     Optionally a steam purge may be used to clean the piercer unit cavity  86 , support surface  82 , and clamping member  100 . Steam is directed through the inlet piercer  123 . The steam purge may be carried out with the piercer body  121  in the raised or lowered position. In addition, it may be carried out automatically after each dispensation cycle and or carried out from time to time under either manual user control or automatic control of the controller. A steam purge may also be used during the dispensation cycle when the cartridge  70  is in the dispensation position to dry out the cartridge  70  and to help drive out any remaining liquid in the cartridge  70 .