Abstract:
A juice extractor ( 100 ), in particular for fruit and vegetable, comprising a rotatable grating disk ( 106 ), a filter sieve ( 108 ) surrounding the grating disk ( 106 ), a feed tube ( 114   a,    114   b ) arranged above the grating disk ( 106 ), and a food pusher ( 116 ) insertable into the feed tube ( 114   a,    114   b ) to press food, in particular fruit and vegetable, onto the grating disk ( 106 ), wherein the food pusher ( 116 ) is hollow with an opening on its side and the feed tube ( 114   a,    114   b ) has an corresponding opening, such that pulp generated during grating food may enter the food pusher ( 116 ). Separate containers for collecting pulp become thus obsolete. This allows for a more compact design of juice extractors ( 100 ).

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to a juice extractor, in particular for fruit and vegetable, comprising a rotatable grating disk, a filter sieve surrounding the grating disk, a feed tube arranged above the grating disk, and a food pusher insertable into the feed tube to press food, in particular fruit and vegetable, onto the grating disk. 
       BACKGROUND OF THE INVENTION 
       [0002]    In juice extractors using a grating disk, juice is extracted from e.g. a fruit or a vegetable by pressing it onto the rotating grating disk, which grates material from the surface of the fruit or vegetable at the same time releasing the juice. The grated material and the juice are thrown upwardly and outwardly by centrifugal force against the surface of a filter surrounding the grating disk. The pulp carries on over the edge of the filter and is caught in a suitable receptacle. The finely filtered juice passes through the filter into another receptacle. In general, juice extractors have an inlet piece opening out just over the grating disk and having a diameter smaller than the grating disk in order to ensure that the food to be processed is held against the rotation of the grating disk. In order to make good use of the surface of the grating disk the diameter of the inlet piece is, in general, only slightly smaller than the diameter of the grating disk. 
         [0003]    Examples for juice extractors are inter alia described in U.S. Pat. No. 6,813,997 B1. They comprise a pushing element, a top cover, a disc blade, a machine body and a residue container for collecting the pulp. If vegetables and fruit are placed into the feeding cylinder and the pushing component is inserted into the feeding cylinder the fruit and vegetables are pressed against the toothed blade of the blade disc. There, the fruit and vegetables are crushed into juice and pulp. The juice is filtered by a filter, so that the purified juice is collected into a container, whereas the pulp is thrown into the residue container. 
         [0004]    It is an object to provide a juice extractor with a compact design. 
       SUMMARY OF THE INVENTION 
       [0005]    This object is achieved by a juice extractor, in particular for fruit and vegetable, comprising a rotatable grating disk, a filter sieve surrounding the grating disk, a feed tube arranged above the grating disk, and a food pusher insertable into the feed tube to press food, in particular fruit and vegetable, onto the grating disk, characterized in that the food pusher is hollow with an opening on its side and in that the feed tube has an corresponding opening, such that pulp generated during grating food may enter the food pusher. 
         [0006]    By providing space inside the food pusher for collecting the pulp no separate container for collecting the pulp is necessary any more, thus allowing for a compact design of the juice extractor that needs very little space. Every time, new food is fed into the feeding tube, the food pusher will be extracted out of the feeding tube to fill in the fresh food. If necessary every time, the food pusher can be emptied from the pulp inside it within seconds. Then, the pusher will be inserted again into the feed tube to push the food against the grating disk for extracting juice, while simultaneously collecting the pulp coming in through the openings in the side of the pusher and the feed tube. Preferably, the openings in the feed tube and the food pusher are more or less commensurate and arranged to be positioned one on the other. The size of the openings will be chosen to collect a maximum of pulp while still efficiently guiding the food through the feed tube and pressing it against the grating disk. 
         [0007]    In some preferred embodiments of the present invention, the juice extractor further comprises a cover element covering the filter sieve and the part of the feed tube with the opening, the cover element having a deflecting element to deflect pulp during grating through the openings into the food pusher. In other preferred embodiments, the feed tube has a deflecting element to deflect pulp during grating through the openings into the food pusher. The one or more deflecting elements have a function comparable to a wall for a ball. The pulp sputtered around by centrifugal forces splashes against the deflecting element and “rebounds” from the deflecting element into another direction. The deflecting element is oriented to deviate the pulp in direction of the side openings of the feed tube and the food pusher. 
         [0008]    Advantageously, the feed tube has a scraper element to scrape pulp from the filter sieve&#39;s inner side. The scraper element has two main advantageous functions. By scraping pulp from the filter sieve&#39;s inner side, it avoids clogging of the filter sieve by the pulp. Besides, the scraped pulp can be additionally collected inside the food pusher. Apart from the feed tube, the scraper element can be arranged on some cover element or housing of the juice extractor as well. The effect of the scraper element can be enhanced by using more than one scraper element. Preferably, the presence of a scraper element is combined with the presence of a deflecting element to further improve the collecting efficiency of the juice extractor according to the present invention. 
         [0009]    In preferred embodiments, the feed tube is designed to be rotated between a first position for introducing food and grating it and a second position, wherein the scraper element abuts against the inner side of the filter sieve. This allows for scraping pulp from the filter sieve only when necessary, e.g. when clogging is imminent. The other time, the juicing and filtering can proceed unimpeded by the scraper element. Preferably, the feed tube has a resilient element forcing the tube back from the second into the first position. So, the default position is the position for juice extraction. When cleaning of the filter sieve is needed, the feed tube may be e.g. manually rotated around a certain angle, until the scraper element is in scraping position against the inner side of the filter sieve and hold there during the scraping of the pulp. As soon as enough pulp has been removed from the filter sieve, the feed tube is released and moves back into the juicing position. This makes the juice extractor quite easy to handle for cleaning. No longsome interruption of the juicing process is necessary for cleaning the filter sieve. 
         [0010]    Advantageously, the filter sieve and the grating disk are integral, i.e. coupled in a way with each other, that when the grating disk is rotating, the filter sieve is rotating as well, together with the grating disk. This considerably enhances the centrifugal forces acting on the juice and the pulp. In particular the pulp will be easier to collect. In case of the presence of a scraper element, with only one scraper element and without any additional driving means, it is possible to clean the whole circumference of the inner side of the filter sieve. 
         [0011]    Preferably, the food pusher and/or the feed tube has stopping means ensuring that the food pusher and the feed tube cannot be rotated with respect to each other. This makes sure that the opening in the side of the feed tube and the opening in the side of the food pusher are always arranged with respect to each other to provide a constant width, preferably the largest possible width. 
         [0012]    Advantageously, the food pusher comprises a slidable sleeve encompassing the food pusher, the sleeve being slidable between a first position closing the opening and a second position leaving the opening in the side of the food pusher open. The sleeve is in the second position, when the food pusher is inserted into the feed tube to push the food against the grating disk and collect the pulp. It is preferable to displace the sleeve into the first position, when extracting the food pusher from the feed tube to avoid spilling accidentally the pulp. For emptying the food pusher from the pulp, the sleeve can be displaced again into the second position, in which the opening in the side of the food pusher is open. Preferably, the food pusher comprises a resilient element forcing the sleeve back from the second position into the first position to assist and facilitate the displacement of the sleeve and avoidance of unintentional spilling of the pulp from inside the food pusher. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    A detailed description of the invention is provided below. Said description is provided by way of a non-limiting example to be read with reference to the attached drawings in which: 
           [0014]      FIGS. 1   a,b  show a first embodiment of a juice extractor in exploded view; 
           [0015]      FIGS. 2   a - d  show a food pusher in different positions; 
           [0016]      FIGS. 3   a,b  show the juice extractor of  FIGS. 1   a,b  in a partially cut view in a cleaning position with and without food pusher; 
           [0017]      FIGS. 4   a,b  show the juice extractor of  FIGS. 1   a,b  in a partially cut view in a juicing position with and without food pusher; and 
           [0018]      FIGS. 5   a,b  show a second embodiment of a juice extractor in exploded view. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0019]    The present invention will be explained more in detail with respect to two different juicers. A first juicer  100  is shown in an exploded view in  FIG. 1   a.  The juicer  100  comprises a housing  102  that contains a motor (not shown) for rotatably driving the grating disk  106 . The housing  102  has furthermore the function to receive the juice of fruits or vegetables that have been grated by the grating disk  106  and centrifuged and filtered by the filter sieve  108 . The fresh juice is than poured into e.g. a drinking glass through the spout  104 . The housing  102  comprises a switch for switching the juicer  100  on or off and change the velocity of the grating disk  106 . 
         [0020]    The grating disk  106  and the filter sieve  108  are integral and inserted in the housing  102 . When the grating disk  106  rotates around its middle axis, the filter sieve  108  rotates as well. This improves the effect of the centrifugal forces acting on the juice and the pulp and, thus, improves the effect of separation of juice on the one hand and pulp on the other hand. The grating disk  106  and the filter sieve  108  being an integral component, this simplifies assembling and disassembling the juicer  100  for the user. 
         [0021]    The housing  102  with the filter sieve  108  and the grating disk  106  is closed by the cover  112  to avoid that juice and pulp are ejected out of the juicer  100 . The cover  112  is connected with the feed tube  114  through which fruits or vegetable are fed to the grating disk  106 . To improve the grating efficiency, the fruits or vegetables are pushed against the grating disk  106  with help of the food pusher  116 . The food pusher  116  is surrounded with a sleeve  136  and a spiral spring  118 . Preferably, the cover  112  is transparent to allow the user to look into the juicer  100 . 
         [0022]    In  FIG. 1   b,  the assembly of the cover  112  and the feed tube  114  is shown more in detail. The feed tube consists of two main parts, an upper part  114   a  protruding to the exterior of the juicer and a lower part  114   b  protruding to the interior of the juicer. The lower part  114   b  contains the opening  124  through which pulp can enter inside the food pusher. Adjacent to the opening  124  are the deflecting element  120  and the scraper element  122 . The deflecting element  120  works similarly to a reflector for the pulp accelerated against it during juice extraction and deviates the pulp in direction of the opening  124 . During juice extraction, the scraper element  122  assists the deflecting element  120  in deviation pulp in direction of the opening  124 . During cleaning, the scraper element  122  is run along the inner side of the filter sieve to scrape off pulp that has accumulated there and clogs the filter sieve. 
         [0023]    The means for rotating the feed tube into the cleaning or the juice extracting position are provided on the upper part  114   a  of the feed tube. A peripheral protrusion  130  cooperates with the abutment  144 , the abutment  144  being part of the cover  112 , to define a maximum angle of rotation. In the present example, the feed tube  114   a,b  may be rotated by approximately 80° around its middle axis to be either in the cleaning position or in the juicing position (see also  FIGS. 3   a,b,    4   a,b ). The default position is the juicing position. To provide an automatic switch back into the default position from the cleaning position, the upper part  114   a  of the feed tube and the cover  112  are coupled with each other by a spring  126 . One end of the spring  126  is fixed on the upper part  114   a  of the feed tube in the protruding groove  132 , the other end of the spring  126  is fixed to the cover  112  (see also  FIGS. 3   a,b,    4   a,b ). The spring  126  is oriented in such a way that the rotation of the feed tube  114   a,b  is in the direction against the spring force. As soon as the user releases the feed tube  114   a,b,  the spring force moves it back into the juicing position. 
         [0024]    Both parts  114   a,    114   b  of the feed tube show a longitudinal protrusion  128 . This longitudinal protrusion  128  cooperates with a corresponding groove in the food pusher to avoid that the food pusher and the feed tube and with them their openings are skewed relatively to each other. This would lead to a smaller or even closed resulting opening to the inner of the food pusher and would lower the efficiency of collecting the pulp or even prevent it. 
         [0025]    The food pusher  116  is shown more in detail in  FIGS. 2   a - d.    FIGS. 2   a,b  show the food pusher  116  during assembly form different perspectives,  FIGS. 2   c,d  show the assembled food pusher  116  from different perspectives. 
         [0026]    The food pusher  116  has an opening  134  on its side to collect pulp inside the food pusher  116 . To avoid spilling the pulp contained inside the food pusher  116  when taking it out of the juicer, e.g. for emptying it, the food pusher is surrounded by a sleeve  136 . The sleeve  136  can be arranged in two different positions. The first and default positions is the one shown in  FIGS. 2   c,d,  where the sleeve  136  covers the opening  134  of the food pusher  116 . In the other position, the sleeve  136  is moved to the other end of the food pusher  116 , thus freeing the opening  134 . By providing the spring  118  around the food pusher  116 , the sleeve  136  has to be moved against the spring force from the first into the second position, and as soon as the user releases the sleeve  136 , it moves back into the first position due to the force of spring  118 . The sleeve  136  is preferably made from metal to make it very thin. The food pusher  116  as well as the feed tube  114  is preferably made from plastic material that is easily cleaned and low cost. 
         [0027]    Both, the sleeve  136  and the food pusher  116  have a longitudinal groove  138 ,  140  that cooperates with the longitudinal protrusion  128  of the feed tube  114   a,b  shown in  FIG. 1   b.  During juicing, when fruits or vegetables are pressed against the grating disk with the bottom  142  of the food pusher  116 , and during cleaning it is thus always ensured that the opening  134  of the food pusher  116  and the opening  124  of the feed tube  114   a,b  (see  FIG. 1   b ) stay aligned for optimal collecting of pulp. 
         [0028]    It will be noted, that besides pressing food against the grating disk, an important function of the bottom  142  of the food pusher  116  is to allow removing the collected pulp by removing the food pusher  116  out of the feed tube. The food pusher  116  can than be emptied e.g. by sliding the sleeve  16  away to open the opening  134  and removing the pulp through the opening  134 . Another possibility of emptying the food pusher  116  is to remove the pulp through the upper opening  146  of the food pusher  116  by turning the food pusher  116  over. 
         [0029]      FIGS. 3   a,b  show the juicer  100  in the cleaning position without food pusher ( FIG. 3   a ) and with food pusher  116  ( FIG. 3   b ). To change the position of the feed tube  114   a,b  from the juicing position into the cleaning position, it has to be turned in direction of the arrows and to be held there. Otherwise, the spring  126  would force the food tube  114   a,b  back into the juicing position. Thanks to the stopping elements longitudinal protrusion  128  in the feed tube  114   a,b  and corresponding groove in the food pusher  116 , the feed tube  114   a,b  and the food pusher  116  do not get askew to each other during the change of position from juicing position and cleaning position, and the openings of the feed tube  114   a,b  and of the food pusher  116  stay aligned. 
         [0030]    After cleaning of the filter sieve and release of the feed tube  116  by the user, the feed tube  116  returns along the direction of the arrows into the juicing position as is shown in  FIGS. 4   a,b,  with inserted food pusher  116  in  FIG. 4   b  and without food pusher in  FIG. 4   a.  In the juicing position, the filter sieve  108  can be utilized on its whole circumference for filtering. The scraper element  122  assists the deflecting element  120  in deviating the pulp in direction of the openings of the feed tube  114   a,b  and the food pusher  116 . The deflecting effect can be optimized for the respective juicer by adapting in particular the curvature and the angle of the deflecting element  120  with respect to the opening of the feed tube  114   a,b.    
         [0031]    In the cleaning position (see  FIGS. 3   a,b ), the scraper element abuts with the inner side of the filter sieve  108 . As the grating disk  106  together with the filter sieve  108  continues to rotate, the scraper element  122  removes the pulp along the whole inner circumference of the filter sieve  108 . The removed pulp is partly deflected immediately in direction of the openings of the feed tube  114   a,b  and the food pusher  116  and is collected inside the food pusher (see  FIG. 3   b ). Partly it falls down on to the grating disk  106  and is grated and centrifuged once more. This considerably improves the efficiency of extracting juice from the provided fruits or vegetables. If the user moves the feed tube  114   a,b  into the cleaning position while having removed the food pusher  116 , all the pulp will be grated and centrifuged again (see  FIG. 3   a ). 
         [0032]    In juicers like shown in the present example with a cylindrical filter sieve  108 , the juicing efficiency is inherently high, because the residence time of the pulp in the receptacle formed by the grating disk  106  and the filter sieve  108  is high. A drawback is, that the pulp accumulates on the inner side of the filter sieve and clogs the filter sieve. The filter sieve  108  of the juicer  100  shown in  FIGS. 1 to 4  must be cleaned form pulp on the average after two to three refills with e.g. apples or carrots. The user does not need to interrupt the juice making to disassemble the juicer  100  for cleaning the filter sieve  108  as with former juicers. The users just needs to rotate the feed tube  114   a,b  for some seconds into the cleaning position to free the inner side of the filter sieve  108  from clogging pulp. This can be done with the food pusher  116  still inside the feed tube  114   a,b  to collect pulp and dispose of it, when removing the food pusher  116  to add more fruits or vegetables into the juicer  100 . Thanks to the slidable sleeve around the food pusher  116  mentioned before, no pulp will be spilled during removal of the food pusher  116 . This can also be done with the food pusher  116  already removed and e.g. while filling new fruits and vegetables into the feed tube  114   a,b.    
         [0033]    When optimizing the scraper element  122  for the respective juicer  100 , one will consider optimizing the angle of the scraper element  122  and its pressure against the inner side of the filter sieve  108  to efficiently remove the pulp without pressing some of the pulp through the filter sieve  108  and by this staining the juice with pulp. To accommodate also persons who like juice with pulp, it is advantageous to provide various scraper elements or filter sieves  108  with various diameter or larger and smaller holes to have more or less pulp getting into the juice on the exterior of the filter sieve  108 . 
         [0034]      FIGS. 5   a,b  show a further example of a juicer  200  with pulp collecting pusher. The juicer  200  has not a cylindrical, but a frusto-conical filter sieve  208 . Frusto-conical filter sieves have the advantage that they do not clog as fast as cylindrical filter sieves, but the juice extraction efficiency is less high because of shorter residence times of the pulp. 
         [0035]    The juicer  200  comprises a motor block  202  for driving the grating disk  230  and the filter sieve  208  connected to the grating disk  230 . The juice filtered through the filter sieve  208  is collected in the receptacle  204  and poured into a glass or a bottle or else through the spout  206 . On the filter sieve  208  and the grating disk that are inserted in the receptacle  204  is place an assembly of a cover  222  with a feed tube  210  that is shown more in detail in  FIG. 5   a.  The feed tube  210  as well as the food pusher  212  has openings  214 ,  216  for collecting the pulp inside the food pusher  212 . In the present example, several openings are provided to collect pulp coming from all sides. During centrifuging, the filter sieve  208  hurls the pulp upwards. The pulp then falls on the peripheral deflecting element  218  of the lower part  210   b  of the feed tube, from where it slides into the food pusher  212 . The pulp can also first be thrown against the inner side of the cover  222  or against the scraper elements  220 , from where the pulp falls into the food pusher  212  or first onto the deflecting element  218 . 
         [0036]    From time to time, the feed tube  210  made from the lower part  210   b  with the openings  216 , the scraper elements  220  and the deflecting element  218  and from the upper part  210   a  guiding the food pusher  212  may be rotated around its middle axis. Then, the scraper elements  220  remove the pulp adhering at the inner walls of the cover  222 . Part of the pulp falls onto the deflecting element  218  and then into the food pusher  212 . Part of the pulp is centrifuged again, thus extracting more juice. Because the openings  214 ,  216  in the food pusher  212  and in the feed tube  210  are so large stopping elements for aligning the openings  214 ,  216  like in the previous example are not necessary. 
         [0037]    The food pusher of the present example has a bottom  226  that is a sieve. To extract even more juice, the pulp inside the food pusher  212  can be pressed against the sieve bottom  226  with the help of a pulp pusher  228  that is dimensioned to be insertable into the food pusher  212 . 
         [0038]    As in the previous example, the food pusher is provided with a sleeve  224  to avoid spilling the pulp when removing the food pusher  212 . When the food pusher  212  is inserted in the feed tube  210 , the sleeve  224  is hold by the upper rim of the feed tube  210 . Due to gravitation, the sleeve  214  slides down the food pusher  212 , when it is removed for adding fruits or vegetables and eventually for disposing of the pulp, and closes the openings  214 . 
         [0039]    Although having described several preferred embodiments of the invention, those skilled in the art would appreciate that various changes, alterations, and substitutions can be made without departing from the spirit and concepts of the present invention. The invention is, therefore, claimed in any of its forms or modifications with the proper scope of the appended claims. For example various combinations of the features of the following dependent claims could be made with the features of the independent claim without departing from the scope of the present invention. Furthermore, any reference numerals in the claims shall not be construed as limiting scope. 
       LIST OF REFERENCE NUMERALS 
       [0000]    
       
           100  juicer 
           102  housing 
           104  spout 
           106  grating disk 
           108  filter sieve 
           110  switch 
           112  cover 
           114   a,b  feed tube 
           116  pusher 
           118  spring 
           120  deflecting element 
           122  scraper element 
           124  opening 
           126  spring 
           128  longitudinal protrusion 
           130  peripheral protrusion 
           132  protruding groove 
           134  opening 
           136  sleeve 
           138  groove 
           140  groove 
           142  bottom 
           144  abutment 
           146  opening 
           200  juicer 
           202  motor block 
           204  juice receptacle 
           206  spout 
           208  filter sieve 
           210   a,b  feed tube 
           212  pusher 
           214  opening 
           216  opening 
           218  deflecting element 
           220  scraper element 
           222  cover 
           224  sleeve 
           226  sieve bottom 
           228  pulp pusher 
           230  grating disk