Patent Publication Number: US-2007107609-A1

Title: Juicer

Description:
TECHNICAL FIELD  
      This invention concerns a juicer, that is a machine for extracting the juice from fruit and vegetables. Such machines are used domestically, and also commercially in restaurants, cafes and juice bars.  
     BACKGROUND ART  
      Juicers receive fruit or vegetables, either whole or cut into a suitable size. Where the skin is unpalatable or undesired it must be removed first. Juicers operate in different ways to extract the juice, but one popular way is by grating or shredding the fruit, separating the resulting pith and juice, and then dispensing the juice.  
      Citrus juicers extract the juice from cut citrus fruit without removing the peel, and generally operate in a different manner to other juicers. In citrus style juicers the cut surface of the fruit is pressed onto a pyramidal hub and then squeezed and rotated relative to the hub to convert almost the entire contents of the fruit to liquid. The peel is then discarded.  
     DISCLOSURE OF THE INVENTION  
      The invention is a juicer for fruit and vegetables, comprising:  
      an electric motor having a driven output shaft;  
      a shredder mounted for rotation about its axis to the output shaft of the motor;  
      a feed tube to deliver pieces to be juiced to the shredder for juicing;  
      where the feed tube has an inner diameter of more than 75 mm, and three, or more, inwardly directed formations are arranged to constrict the interior of the feed tube.  
      The inner diameter of the feed tube may be large enough for a typical apple to pass through it whole; it may be 85 mm or more. The inwardly directed formations serve to prevent the insertion of a hand or arm into or through the feed tube despite the fact that the diameter is large enough for a typical apple to pass through.  
      The inwardly directed formations may be arranged about a collar at the top of the feed tube. Alternatively, the formations may be integrated into the walls of the feed tube. The formations may comprise ribs running down the collar or down the length of the walls of the feed tube. In a particularly preferred embodiment the feed tube has nine equispaced inwardly directed ribs, each 0.5 mm high or more. In this way the clear inner diameter is reduced to 75 mm or a little less.  
      The free end of the ribs running down the length of the feed tube may be a sharp edge to provide a cutting blade that is able to cut the pieces delivered by the feed tube to the shredder. The height of these ribs may increase down the length of the feed tube. This arrangement helps to prevent the piece from bouncing near the shredder wall by jamming the piece within the feed tube.  
      The shredder may have toothed sidewalls with axial symmetry, and it may be frusto-conical in shape. It may be mounted with the narrow end of the frusto-conical shredder to the output shaft of the motor and oriented with the axis of the frusto-conical shredder offset from vertical. It may also be mounted on bearings arranged around its wide end. The teeth may be arranged on the inner surface of the shredder. A frusto-conical sieve may extend from the wide end of the frusto-conical shredder. The lower end of the feed tube may be positioned adjacent the toothed sidewall of the shredder.  
      A lid assembly may enclose the frusto-conical sieve. The sidewalls of the sieve may be offset to the sidewalls of the shredder. It may provide a spout extending downwardly from sieve to dispense juice into a beaker. It may also provide a pulp receiving chamber offset to one side of the sieve. Optionally, the configuration of the offset of the axis of the shredder and the offset between the sidewalls of the shredder and sieve together with the rotating action of the shredder throws the pulp and juice up out of the shredder into the chamber and spout respectively.  
      A further invention provides fans blades around the top edge of the sieve to clear pulp from accumulating there and to move it into the pulp receiving chamber. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      An example of this invention will now be described with reference to the accompanying drawings, in which:  
       FIG. 1  is a sectional view through a juicer;  
       FIG. 2  is a plan view into the feed tube;  
       FIG. 3  is a pictorial view of the feed tube and pusher;  
       FIG. 4  is a plan view of an alternate feed tube;  
       FIG. 5  is a sectional view of the feed tube of  FIG. 4 ;  
       FIG. 6  is a detailed sectional view of the juicer of  FIG. 1  in use;  
       FIG. 7  is pictorial view of a conical sieve fitted with fan blades; and,  
       FIG. 8  is a partial section view of a shredder, sieve and pulp collecting chamber.  
    
    
     BEST MODE OF THE INVENTION  
      The juicer  10  is designed to sit on a counter top and comprises a main unit  20 , a lid assembly  40  and a juice receiving beaker  60 .  
      An electric motor  22  is mounted inside the main unit  20 , and has its output shaft  23  lying on axis  24  offset from the vertical. The output shaft is connected to a shredder  25 . Shredder  25  is generally frusto-conical in shape and is also aligned with axis  24 . It is oriented downwards and mounted at its narrow end  26  to the output shaft  23 . It is also mounted on bearings  27  supported by the housing of the main unit  20 . A generally frusto-conical sieve  28  extends above the upper part of the shredder. A lateral extension  29  of the upper part of the shredder  25  extends to cover over the bearings  27  and the join with the lid assembly  40 .  
      The lid assembly  40  encloses the frusto-conical sieve  28 . It provides a spout  41  extending downwardly from sieve  28  to dispense juice into beaker  60 . It also provides a pulp receiving chamber  42  offset to one side of the sieve  28 , and a fruit or vegetable receiving feed tube  43  which extends vertically down through the lid into the sieve  25 . A ‘pusher’  44  is provided with a handle  45  and a closed tubular body sized to sit inside tube  43 .  
      Referring now to  FIGS. 2 and 3 , the fruit or vegetable receiving tube  43 , or feed tube, is seen to have an inner diameter of 85 mm. 85 mm is large enough for many apples to be inserted down the feed tube whole. Nine ribs, one of which is marked  100 , are each 5.5 mm high and are equispaced around the inner face of a collar  101  mounted at the upper end of the feed tube. The nine ribs  100  reduce the clear inside diameter of the feed tube to 74 mm. This improves safety by restricting the feed tube to the extent that it is difficult for user to insert a hand down it. The body of the pusher  44  is shaped  102  to accommodate the ribs, as shown in  FIG. 3 , so that it can enter the feed tube  43  and push the fruit or vegetables down to the lower end. The space between the nine ribs is 24.5 mm. In a further example shown in  FIG. 4 , the ribs  100  of the feed tube  43  may extend down a portion of the length of the feed tube  43  and also increase in height as shown in  FIG. 5 . The free ends  82  of the ribs  100  may be sharp and thin so as to form blades  80 . In this way, as the fruit or vegetable is pushed down the feed tube  43 , it becomes trapped and reduces the amount that it bounces at the sidewall of the shredder.  
      Referring in addition to  FIG. 6  the juicer will be now be described in greater detail together with its operation and use. The inner surface  30  of shredder  25  is covered with teeth  31  around its sidewalls  32  and on surface  33  of the narrow end of the shredder  25 . Teeth  31  are oriented to tear when the shredder  25  is spun about axis  24  in the direction indicated by arrow  34 . The lower end  47  of feed tube  43  enters the shredder  25  and opens all along the sidewall  32  and partly along the surface  33  at the narrow end of the shredder  25 . When the motor  22  is energised its output shaft  23  spins, causing the entire shredder  25  to spin about axis  24  in the direction indicated by arrow  34 .  
      Referring now to  FIG. 7  sieve  28  is seen to have an upper rim  110  of plastics material bearing  10  integrally moulded fan blades, one of which is indicated at  120 .  
      In use, fruit or vegetables are whole or cut into pieces small enough to enter tube  43 . Because the inner diameter of the feed tube  43  is 85 mm a whole apple  50  can pass through it and used to describe this example. The apple  50  is pushed into the top of the feed tube  43 , passing through the collar  101  and being scored by ribs  100  if large enough to engage them. The apple  50  can then fall freely through the remainder of the feed tube  43 . Pusher  44  can be used to help the apple past the ribs  100  if necessary. The motor  22  is connected to the mains electricity supply by means of a conventional lead and plug, and the motor  22  is energised. The apple  50  is pushed down feed tube  43  by pusher  46  and exit at the lower open end  47 . Here the apple  50  is shown to meet the rotating teeth  31 , and are torn up, converting them to pulp and juice.  
      The rotating action of the shredder  25  and the offset angle of axis  24  throws the pulp and juice up out of the shredder in a predicable direction. The sieve wall is offset at a small angle, say 8°, to the shredder wall. This has the effect of slowing down the exit of pulp and juice out of the shredder. The pulp is thrown up in direction  51  out of the shredder  25  and sieve  28 . Chamber  42  is located to receive and collect the pulp  52 , and the lid  40  is shaped to guide the pulp into the chamber  42 . At the same time the juice is thrown up the sides of sieve  28  where it passes through in the direction indicated by arrows  53 . Any pulp entrained in the juice is collected on the surface of sieve  28  where it falls back into the shredder and is again thrown out. The juice  54  is drained away by spout  41  and collected in beaker  60 .  
      Referring further to  FIG. 8  the fan blades  120  around the upper rim  110  of sieve  28  stir up strong air currents  140  to carry pulp into the pulp receiving chamber  42  and prevent it from accumulating and blocking the passage from the sieve  28  to the pulp receiving chamber  42 . An air vent  160  above the pulp receiving chamber  42  allows the spent air  150  to escape.  
      The multiple bearings  26  and  27  serve to stabilize the shredder against the force exerted down on it by the pusher, and this in turn protects the bearings of the motor  22 , the overall effect is to provide longevity to the moving parts. The offset axis  24  allows the pieces to be introduced vertically and be delivered to the sidewall  32  of the shredder  25 . Tearing of the apple  50  occurs by the transverse movement of the teeth  31  across substantially the entire open end of the feed tube  43 , causing efficient shredding. The lateral movement of the teeth  31  also tends to entrain the apple  50  and prevents it from spinning.  
      It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.