Abstract:
An automatic juicer turns and pushes an upward facing juicing cone into a fruit for releasing juice. The juicer includes a base containing a motor, gear and shaft assembly. A fixed guide extends upward from the base and inner and outer shafts reside inside the fixed guide and are driven by the motor and gear assembly to rotate and advance the juicing cone into the fruit. The inner shaft includes threads to vertically advance and retreat a shaft nut and the outer shaft rotates with the inner shaft, but is lifted by the shaft nut when the inner shaft turns. The juicing cone releases the juice and a stationary bowl catches the juice.

Description:
The present application is a Continuation In Part of U.S. patent application Ser. No. 12/206,964 filed Sep. 9, 2008, U.S. patent application Ser. No. 12/406,314 filed Mar. 18, 2009, and U.S. patent application Ser. No. 12/550,232 filed Aug. 28, 2009 which applications are incorporated in their entirety herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to juice extractors and in particular to electric juice extractors. 
     Juice extractors are commonly used to extract juice from, for example, oranges. Known manual juice extractors comprise a bowl with a raised conical ridged center, called a juicing cone. A user cuts a fruit in half, and pushes and rotates the exposed cut side down over the juicing cone. The juice is thereby released into the bowl. 
     Manual juice extractors have been largely replaced by electric juicers. Various electric juicers exist, including centrifugal juicers which include blades and spins to separate the juice from pulp, masticating which grinds and then squeezes the juice from the pulp, and simple citrus juicers which resemble a manual juicer but include an electric motor to rotate the juicing cone. 
     While the known juicers are often satisfactory, users still desire a simple automatic juicer which is not as rough on the fruit as the centrifugal or masticating juicers, but does not require the users to manually push the fruit on the electrically turned juicing cone. U.S. patent application Ser. No. 12/206,964 filed Sep. 9, 2008, U.S. patent application Ser. No. 12/406,314 filed Mar. 18, 2009, and U.S. patent application Ser. No. 12/550,232 filed Aug. 28, 2009 by the present applicant discloses automated juicers providing many of the benefits desired, however, further development resulted in an alternative embodiment which simplifies manufacturing. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention addresses the above and other needs by providing an automatic juicer which turns and pushes an upward facing juicing cone into a fruit for releasing juice. The juicer includes a base containing a motor, gear and shaft assembly. A fixed guide extends upward from the base and inner and outer shafts reside inside the fixed guide and are driven by the motor and gear assembly to rotate and advance the juicing cone into the fruit. The inner shaft includes threads to vertically advance and retreat a shaft nut and the outer shaft rotates with the inner shaft, but is lifted by the shaft nut when the inner shaft turns. The juicing cone releases the juice and a stationary bowl catches the juice. 
     In accordance with one aspect of the invention, there is provided an automatic juicer. The juicer includes a base, a lid attached to the base and openable to allow fruit to be placed in the juicer; a center column assembly attached to the base and including a collet fixed to the base and having internal threads, and a motor, gear and shaft mechanism inside the juicer and advancing and retreating vertically as a unit. The motor, gear and shaft mechanism includes a motor in the base, a gear set in the base and engaging the motor, and a shaft assembly extending above the base. The shaft assembly includes an outer shaft threadably engaging the collet for vertically advancing and retreating when turned by the motor through the gear set, and an inner shaft rotating inside the outer shaft and advancing and retreating vertically with the outer shaft. An upward facing juicing cone is attached to the inner shaft and rotates and advances vertically with the inner shaft into a fruit. A bowl resides under the juicing cone and is attached to the base. The juicing cone thereby rotates and pushes into a fruit for releasing juice from the fruit to be caught in the bowl. 
     In accordance with another aspect of the invention, there is provided an automatic juicer. The juicer includes a base containing a motor and a gear set engaging the motor. A lid is attached to the base and is openable to allow fruit to be placed in the juicer. A center column assembly is attached to the base and includes a collet fixed to the base. An outer shaft threadably engages the collet and vertically advances and retreats when turned by the motor through the gear set. An inner shaft rotates with the outer shaft and advances and retreats vertically with the outer shaft when turned by the motor. A bowl is attached to the base and an upward facing juicing cone is attached to the inner shaft and rotates and advances vertically with the inner shaft, rotating and pushing into a fruit for releasing juice from the fruit to be caught in the bowl. A non-rotating strainer advances and retreats vertically with the juicing cone and knife edges on a bottom surface of the juicing cone clear pulp blocking the strainer. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
       The above and other aspects, features and advantages of the present invention will be more apparent from the following more particular description thereof, presented in conjunction with the following drawings wherein: 
         FIG. 1A  is a juicer according to the present invention with a closed lid. 
         FIG. 1B  is the juicer according to the present invention with an open lid. 
         FIG. 2  is a cross-sectional view of the juicer according to the present invention with a juicing cone in a down position and the lid closed. 
         FIG. 3  is a cross-sectional view of the juicer according to the present invention with the juicing cone in an up position and the lid closed. 
         FIG. 4A  is a cross-sectional view of the lid of the juicer. 
         FIG. 4B  is a cross-sectional view of a fruit holder, according to the present invention, of the juicer. 
         FIG. 4C  is a cross-sectional view of the juicing cone, according to the present invention, of the juicer. 
         FIG. 4D  is a cross-sectional view of a strainer, according to the present invention, of the juicer. 
         FIG. 4E  is a cross-sectional view of a bowl, according to the present invention, of the juicer. 
         FIG. 5A  is a cutaway view of a center column assembly of the juicer according to the present invention in the down position. 
         FIG. 5B  is a cutaway view of the center column assembly of the juicer according to the present invention in the up position. 
         FIG. 6  is an exploded view of the center column assembly, according to the present invention, of the juicer. 
         FIG. 7  shows a vertical stop according to the present invention. 
         FIG. 8  shows a strainer key and key way. 
         FIG. 9A  is a side view of an outer column, according to the present invention, of the center column of the juicer. 
         FIG. 9B  is a top view of the outer column, according to the present invention, of the center column of the juicer. 
         FIG. 9C  is a bottom view of the outer column, according to the present invention, of the center column assembly of the juicer. 
         FIG. 9D  is a cross-sectional view of the outer column taken along line  9 D- 9 D of  FIG. 9A . 
         FIG. 9E  is a cross-sectional side view of the outer column taken along line  9 E- 9 E of  FIG. 9C . 
         FIG. 10A  is a side view of an inner (or drive) shaft, according to the present invention, of the center column of the juicer. 
         FIG. 10B  is a top view of the drive shaft of the center column assembly of the juicer. 
         FIG. 10C  is a bottom view of the drive shaft of the center column assembly of the juicer. 
         FIG. 11A  is a side view of an outer shaft guide, according to the present invention, of the center column assembly of the juicer. 
         FIG. 11B  is a top view of the outer shaft guide of the center column assembly of the juicer. 
         FIG. 11C  is a bottom view of the outer shaft guide of the center column assembly of the juicer. 
         FIG. 12A  is a side view of an outer (or driven) shaft, according to the present invention, of the center column assembly of the juicer. 
         FIG. 12B  is a top view of the outer shaft of the center column assembly of the juicer. 
         FIG. 12C  is a bottom view of the outer shaft of the center column assembly of the juicer. 
         FIG. 12D  is a side cross-sectional view of the outer shaft of the center column assembly of the juicer taken along line  12 D- 12 D of  FIG. 12   a.    
         FIG. 13A  is a side view of a lift nut, according to the present invention, of the center column assembly of the juicer. 
         FIG. 13B  is a top view of the lift nut of the center column assembly of the juicer. 
         FIG. 14  shows a second fruit holder with an adjustable seat. 
         FIG. 15A  shows a clutch and gearing assembly according to the present invention in a high speed position. 
         FIG. 15B  shows the clutch and gearing assembly according to the present invention in a high torque position. 
     
    
    
     Corresponding reference characters indicate corresponding components throughout the several views of the drawings. 
     DETAILED DESCRIPTION OF THE INVENTION 
     The following description is of the best mode presently contemplated for carrying out the invention. This description is not to be taken in a limiting sense, but is made merely for the purpose of describing one or more preferred embodiments of the invention. The scope of the invention should be determined with reference to the claims. 
     A juicer  10  according to the present invention is shown with a lid  12  closed in  FIG. 1A  and with the lid  12  open exposing a juicing cone  16  in  FIG. 1B . The lid  12  pivots at hinge  16  and is held closed by latch  18 . A half fruit may be placed over the juicing cone  26  and the lid  12  closed to operate the juicer  10 . 
     A cross-sectional view of the juicer  10  with the juicing cone  26  in a down position and the lid  12  closed is shown in  FIG. 2 , and a cross-sectional view of the juicer  10  with a juicing cone in an up position and the lid  12  closed is shown in  FIG. 3 . The hinge  16  connects the lid  12  to the base  14 , and the latch  18  holds the lids  12  closed during operation of the juicer  10 . The fruit holder  24  includes anti-slip elements on the inside fruit surface to prevent the fruit from rotating inside the fruit holder  24  during operation of the juicer. The anti-slip elements may be spikes, ridges or the like, for example ridges  24   a.    
     The juicer  10  includes a base  14  housing a motor  20  and a gearing assembly  22  (see  FIGS. 15A and 15B  for details). The motor  20  may be manually controlled by a user to operate in a first direction to raise the juicing cone against fruit for about five seconds and then manually controlled to lower the juicing cone, or may be automated to raise the juicing cone against fruit for about five seconds and then automatically reverse. The motor  20  and the gearing assembly  22  may alternatively be controlled by measuring the vertical force of the juicing cone against the fruit, and the motor direction reversed when the force reaches a predetermined level. 
     The juicer  10  includes a fruit holder  24 , the juicing cone  26 , a strainer  28 , and a bowl  29 . The fruit holder  24  is fixed inside the lid  12  and opens with the lid  12 . The juicing cone  26  includes ridges  25  (see  FIG. 4C ) and rises into the fruit and rotates. The ridges  25  cut into the pulp of the fruit to release fruit juice and the rising juicing cone  26  compresses the pulp to further release the juice. The strainer  28  resides under the juicing cone  26  and rises with the juicing cone  26  but does not rotate. The bowl  29  is fixed to the base  14  and does not rise or rotate, and catches the juice released from the fruit. 
     A cross-sectional view of the lid  12  of the juicer  10  is shown in  FIG. 4A , a cross-sectional view of the fruit holder  24 , according to the present invention, of the juicer  10  is shown in  FIG. 4B , a cross-sectional view of the juicing cone  26 , according to the present invention, of the juicer  10  is shown in  FIG. 4C , a cross-sectional view of a strainer  28 , according to the present invention, of the juicer  10  is shown in  FIG. 4D , and a cross-sectional view of a bowl  29 , according to the present invention, of the juicer  10  is shown in  FIG. 4E . The upward facing face of the juicing cone  26  includes the ridges  25  for cutting into the pulp of the fruit and a lower end of the juicing cone  26  includes blades (or scrapers)  27  which scrape against a top surface of the strainer  28  to prevent pulp from blocking the strainer  28  during use. The fruit holder  24  includes a seat  21  for limiting upward movement of the juicing cone  26 , and the juicing cone  26  includes a stop  23  for cooperation with the seat  21 . 
     A cutaway view of a center column assembly  30  of the juicer  10  is shown in the down position in  FIG. 5A  and in the up position in  FIG. 5B , and an exploded view of a center column assembly  30  according to the present invention of the juicer  10  is shown in  FIG. 6 . The center column assembly  30  includes a rotating and vertically translating outer shaft  32 , a stationary (non-rotating and non-translating) outer column  34  attached to the base  14  (see  FIG. 1 ), a spring  36 , a lifting nut  40 , an inner shaft  42  and a guide  48 . The outer shaft  32  lifts and rotates the juicing cone  26 . The spring  36  resides inside the outer column  34  and provides downward force on the outer shaft  32  and/or the lifting nut  40  to bias the outer shaft  32  towards a down position (see  FIGS. 2-4 ). The outer shaft  32  resides outside the inner shaft  42  and is guided by the guide  48  or keyed to rotate with the inner shaft  42  but free to vertically translate. The lifting nut  40  is threaded into the exterior of the inner shaft  42  and is shaped (e.g., is rectangular, square, oval, elliptical or any shape other than round) to prevent the lifting nut  40  from rotating with the inner shaft  42 . A smooth portion  42 ′ at the top of the inner shaft  42  may be provided to allow the lifting nut  40  to disengage from threads  43  of the inner shaft  42  at maximum vertical extension until the rotation of the inner shaft  42  is reversed. The inner shaft  42  is attached to pears  86  and  90  (see  FIG. 15A ). 
     A vertical stop according to the present invention is shown in  FIG. 7 . The juicing cone  26  includes a stop  23  at the peak of the cone, and the fruit holder  24  includes a seat  21  above the stop  23 . The seat  21  limits the vertical movement of the juicing cone  26  to establish a minimum gap G between the ridges  25  and the interior of the fruit holder  24  to prevent or reduce the ridges  25  cutting into the fruit rind. 
     A strainer key  37  and key way  31  are shown in  FIG. 8 . The key  37  resides on an edge of the strainer and engages the key way  31  in the lid  12  and/or bowl  29  to prevent rotation of the strainer  28  so that the blades  27  on the bottom of the juicing cone  26  can scrape pulp from the inside of the strainer  28 , which pulp might otherwise block the strainer  28 . 
     A side view of the outer column  34  of the center column assembly  30  of the juicer  10  is shown in  FIG. 9A , a top view of the outer column  34  is shown in  FIG. 9B , a bottom view of the outer column  34  is shown in  FIG. 9C , a cross-sectional view of the outer column  34  taken along line  9 D- 9 D of  FIG. 9A  is shown in  FIG. 9D , and a cross-sectional view of the outer column  34  taken along line  9 E- 9 E of  FIG. 9B  is shown in  FIG. 9E . The outer column  34  has a square exterior and square (or any non-round) interior  33  with a flange  35  at the base for attaching to the juicer base  14 . The outer column  34  is fixed and neither rotates nor translates. An interior  33  cooperates with the lifting nut  40  to prevent rotation of the lifting nut  40 . The outer column  34  includes a ceiling  37  for cooperation with the spring  36 . While a preferred outer column  34  has a square interior cross-section, a juicer according to the present invention with an outer column without a square interior is intended to come within the scope of the present invention. 
     A side view of a inner shaft  42 , according to the present invention, of the center column assembly  30  of the juicer  10  is shown in  FIG. 10A , a top view of the inner shaft  42  is shown in  FIG. 10B , and a bottom view of the inner shaft  42  is shown in  FIG. 10C . The inner shaft  42  is connected to the motor  20  through the gearing assembly  22  (see  FIG. 2 ) and is rotated by the gearing assembly  22  but does not translate. The inner shaft  42  includes threads  45  on a cylindrical exterior for cooperation with a threaded interior  40 ′ of the lifting nut  40  (see  FIG. 13B ). Because the outer column  34  prevents rotation of the nut  40 , rotation of the inner shaft  42  causes the nut  40  to translate vertically. 
     Aside view of an outer shaft guide  48  according to the present invention, of the center column assembly  30  of the juicer  10  is shown in  FIG. 11A , a top view of the outer shaft guide  48  is shown in  FIG. 11B , and a bottom view of the outer shaft guide  48  is shown in  FIG. 11C . The outer shaft guide  48  is fixed to the top of the inner shaft  42  and rotates with the inner shaft. The outer shaft guide  48  may, for example, include a cylindrical portion  46  which is inserted into the top of the inner shaft  42  and thereby attached using threads, glue, key way, non-round shape, or the like, or be formed as a single piece with the inner shaft  42 . 
     A side view of an outer (or driven) shaft  32 , according to the present invention, of the center column assembly  30  of the juicer  10  is shown in  FIG. 12A , a top view of the outer shaft  32  is shown in  FIG. 12B , a bottom view of the outer shaft  32  is shown in  FIG. 12C , and a side cross-sectional view of the outer shaft  32  taken along line  12 D- 12 D of  FIG. 12   a  is shown in  FIG. 12D . The outer shaft  32  resides over the inner shaft  42  and is rotatably coupled to the inner shaft by cooperation of a non-round interior  32 ′ and the outer shaft guide  48 , and rotated with the inner shaft, but may advance or retreat vertically with respect to the inner shaft  42 . The outer shaft  32  includes a coupling portion  54  for coupling with the juicing cone  26  to lift and rotate the juicing cone  26 . A footing  32   a  reaches out from the bottom of the outer shaft  32  and cooperates with the spring  36  to urge the outer shaft  32  downward when the lifter nut  40  retreats vertically. 
     A side view of the lifting nut  40 , according to the present invention, of the center column assembly  30  of the juicer  10  is shown in  FIG. 13A  and a top view of the lifting nut  40  is shown in  FIG. 13B . The lifting nut  40  has a threaded interior  40 ′ for cooperating with the threads  45  on the inner shaft  42  and a non-round, and preferably square, exterior  41  for cooperation with the interior of the outer column  34  to prevent rotation of the lifting nut  40 . When the inner shaft  42  rotates, the lifting nut  40  advances or retreats vertically to lift or lower the juicing cone  26 . 
     A second fruit holder  24 ′ with an adjustable seat  80  is shown in  FIG. 14  The adjustable seat  80  preferably includes threads which cooperate with the fruit holder  24 ′ to allow adjustment of the gap G between the juicing cone  26  and the fruit holder  24 ′. 
     The gearing assembly  22  (see  FIG. 2 ) according to the present invention is shown in a high speed position in  FIG. 15A  and in a high torque position in  FIG. 15B . The gearing assembly  22  includes a motor  82 , switch  84 , first gears  94  and  96 , second gears  90  and  92 , third gears  86  and  88 , and a spring  98 . The gears  94  and  96  are always engaged. In the relaxed (or UP) position, the spring  98  pushed the gears  90  and  86  upwards, and the gear  90  engages the gear  92  to provide high speed. In the compressed (or DOWN) position, the spring  98  is compressed allowing the gears  90  and  86  to move downward, and the gear  86  engages the gear  88  to provide high torque. The spring  98  further provides a relief from exerting too great a downward force on the gearing assembly  22  or too much upward force on the juicing cone  26 . The springs  98  and  36  (see  FIG.6 ) combine to limit the force exerted on the fruit to preferably between one pound and 50 pounds, and more preferably limit the force exerted on the fruit to between ten pounds and 25 and most preferably limit the force exerted on the fruit to approximately 18 pounds. 
     The direction of the motor is initially to advance the juicing cone into the fruit, and either after a period of time, or when a preset level of resistance is met by the vertically advancing juicing cone, the direction of the motor reverses to vertically retreat the juicing cone from the fruit. 
     While the invention herein disclosed has been described by means of specific embodiments and applications thereof, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope of the invention set forth in the claims.