Abstract:
An automatic juicer turns and pushes an upward facing juicing cone into a fruit for releasing and collecting juice. The juicer includes a base containing a clutch and gearing assembly connected to a motor. A center column assembly rotates and advances the juicing cone. The juicing cone, strainer, and a bowl release and catch the juice. The center column includes an outer column fixed to the base, a rotating drive shaft driven by the motor but not advancing vertically, and a driven shaft which rotates with the drive shaft and advances and retreats vertically. The bowl is fixed to the base. The strainer advances vertically with juicing cone but does not rotate. The juicing cone is attached to the driven shaft and rotates and advances vertically, thereby releasing juice from the fruit. Knife edges on the bottom of the juicing cone scrape pulp from the strainer to prevent clogging.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to juice extractors and in particular the electric juice extractors. 
     Juice extractors are commonly used to extract juice from, for example, oranges. Known manual juice extracts 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. 
     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 and collecting juice. The juicer includes a base containing a clutch and gearing assembly connected to a motor. A center column assembly rotates and vertically advances the juicing cone into the fruit. The juicing cone, strainer, and a bowl release and catch the juice. The center column includes an outer column fixed to the base, a rotating drive shaft driven by the motor but not advancing vertically, and a driven shaft which rotates with the drive shaft and advances and retreats vertically. The bowl is fixed to the base. The strainer advances vertically with juicing cone but does not rotate. The juicing cone is attached to the driven shaft and rotates and advances vertically, thereby releasing juice from the fruit. Knife edges on the bottom of the juicing cone scrape pulp from the strainer to prevent clogging. 
     In accordance with one aspect of the invention, there is provided an automatic juicer. The juicer includes a base, a center column assembly, a juicing cone, a strainer, and a bowl. The base contains a motor and a clutch and gearing assembly connected to the motor. The center column assembly is fixed to the base and includes a vertical outer cylinder (or column) fixed to the base, a drive shaft residing inside the outer cylinder and turned by the motor through the clutch and gearing assembly, a driven shaft, and a nut residing inside the outer cylinder and constrained to not rotate while threadedly cooperating with the rotating drive shaft to advance and retreat vertically. The drive shaft rotates but does not advance or retreat vertically. The driven shaft rotates with the drive shaft and advances and retreats vertically. The nut threadedly cooperates with the drive shaft to advance and retreat vertically when the drive shaft rotates and is vertically coupled to the driven shaft to advance the driven shaft vertically. The bowl is fixed to the base. The juicing cone is attached to the driven shaft and rotates and advances vertically with the driven shaft, thereby releasing juice from the fruit. 
    
    
     
       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. 1  is a juicer according to the present invention. 
         FIG. 2  is a cross-sectional view of the juicer according to the present invention with a juicing cone in an up 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 a down position and the lid closed. 
         FIG. 4  is a cross-sectional view of the juicer according to the present invention with the juicing cone in a down position and the lid open. 
         FIG. 5A  is a cross-sectional view of the lid of the juicer. 
         FIG. 5B  is a cross-sectional view of a fruit holder, according to the present invention, of the juicer. 
         FIG. 5C  is a cross-sectional view of the juicing cone, according to the present invention, of the juicer. 
         FIG. 5D  is a cross-sectional view of a strainer, according to the present invention, of the juicer. 
         FIG. 5E  is a cross-sectional view of a bowl, according to the present invention, of the juicer. 
         FIG. 6  is an exploded view of a 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 tube (or column), according to the present invention, of the center column of the juicer. 
         FIG. 9B  is a bottom view of an outer tube, according to the present invention, of the center column of the juicer. 
         FIG. 9C  is a side view of an outer tube, according to the present invention, of the center column assembly of the juicer. 
         FIG. 9D  is a cross-sectional view of the outer tube taken along line  9 D- 9 D of  FIG. 9A . 
         FIG. 9E  is a cross-sectional view of the outer tube taken along line  9 E- 9 E of  FIG. 9C . 
         FIG. 10A  is a side view of a drive shaft, according to the present invention, of the center column of the juicer. 
         FIG. 10B  is a bottom view of the drive shaft of the center column assembly of the juicer. 
         FIG. 10C  is a top view of the drive shaft of the center column assembly of the juicer. 
         FIG. 11A  is a side view of a nut, according to the present invention, of the center column assembly of the juicer. 
         FIG. 11B  is a top view of the nut of the center column assembly of the juicer. 
         FIG. 12A  is a side view of a driven shaft, according to the present invention, of the center column assembly of the juicer. 
         FIG. 12B  is a bottom view of the driven shaft of the center column assembly of the juicer. 
         FIG. 12C  is a top view of the driven shaft of the center column assembly of the juicer. 
         FIG. 13A  is a side view of a lift tube, according to the present invention, of the center column assembly of the juicer. 
         FIG. 13B  is a bottom view of the lift tube of the center column assembly of the juicer. 
         FIG. 13C  is a top view of the lift tube of the center column assembly of the juicer. 
         FIG. 14  is a cross-sectional view of the lift tube taken along line  14 - 14  of  FIG. 13A . 
         FIG. 15  is a second embodiment of a center column assembly according to the present invention of the juicer. 
         FIG. 16  shows a second fruit holder with an adjustable seat.′ 
         FIG. 17A  shows a clutch and gearing assembly according to the present invention in a high speed position. 
         FIG. 17B  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 in  FIG. 1 , a cross-sectional view of the juicer  10  with a juicing cone in an up position and a lid  12  closed is shown in  FIG. 2 , a cross-sectional view of the juicer  10  with a juicing cone in a down position and the lid  12  closed is shown in  FIG. 3 , and a cross-sectional view of the juicer  10  with a juicing cone in a down position and the lid  12  open is shown in  FIG. 4 . A hinge  16  connects the lid  12  to the base  14 , and a latch  18  holds the lids 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 ′. 
     The juicer  10  includes a base  14  housing a motor  20  and a gearing assembly  22  (see  FIGS. 17A and 17B  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 5 seconds and then manually controlled to lower the juicing cone, or may be automated to raise the juicing cone against fruit for about 5 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. (Can we add anything here? Is there an off the shelf unit you can use?) 
     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. 5C ) 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  26  cone 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. 5A , a cross-sectional view of the fruit holder  24 , according to the present invention, of the juicer  10  is shown in  FIG. 5B , a cross-sectional view of the juicing cone  26 , according to the present invention, of the juicer  10  is shown in  FIG. 5C , a cross-sectional view of a strainer  28 , according to the present invention, of the juicer  10  is shown in  FIG. 5D , and a cross-sectional view of a bowl  29 , according to the present invention, of the juicer  10  is shown in  FIG. 5E . The upward facing face of the juicing cone  26  includes 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 . 
     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 lift tube  32 , a stationary (non-rotating and non-translating) outer tube  34  attached to the base  14  (see  FIG. 1 ), a spring  36 , a driven shaft  38 , a nut  40 , and a drive shaft  42 . The lift tube  32  lifts and rotates the juicing cone  26 . The spring  36  resides inside the outer tube  34  and provides downward force on the driven shaft  38  and/or the nut  40  to bias the center column assembly  30  towards a down position (see  FIGS. 2-4 ). The driven shaft  38  resides inside the drive shaft  42  and is keyed to rotate with the drive shaft  42  but free to vertically translate. The nut  40  is threaded into the exterior of the drive shaft  42  and includes at least one outside notch  44  (see  FIG. 11B ) to engage a vertical rail  39  (see  FIG. 9D ) in the outer tube  34  to prevent the nut  40  from rotating with the drive shaft  42 . A smooth portion  42 ′ at the top of the drive shaft  42  allowing the drive shaft  42  to rotate freely from the nut  40  at maximum extension. 
     A vertical stop according to the present invention is shown in  FIG. 8 . 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 tube (or column)  34  of the center column assembly  30  of the juicer  10  is shown in  FIG. 9A , a bottom view of the outer tube  34  is shown in  FIG. 9B , a side view of the outer tube  34  is shown in  FIG. 9C , a cross-sectional view of the outer tube  42  taken along line  9 D- 9 D of  FIG. 9A  is shown in  FIG. 9D , and a cross-sectional view of the outer tube  34  taken along line  9 E- 9 E of  FIG. 9C  is shown in  FIG. 9E . The outer tube  34  has a cylindrical exterior and cylindrical interior with an outer tube flange  35  at the base for attaching to the juicer base  14 . The outer tube  34  is fixed and neither rotates nor translates. An interior vertical rail  39  runs the length of the interior and cooperates with one of the notches  44  (see  FIG. 11B ) of the nut  40  to prevent rotation of the nut. The outer tube  34  includes a ceiling  37  for cooperation with the spring  36 . While a preferred outer tube  34  has a cylindrical interior and exterior, a juicer according to the present invention with an outer column which is not cylindrical is intended to come within the scope of the present invention. 
     A side view of a drive shaft  42 , according to the present invention, of the center column assembly  30  of the juicer  10  is shown in  FIG. 10A , a bottom view of the drive shaft  42  is shown in  FIG. 10B , and a top view of the drive shaft  42  is shown in  FIG. 10C . The drive 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 drive shaft  42  includes threads  45  on a cylindrical exterior for cooperation with a threaded interior  47  (see  FIG. 11B ) of the nut  40 . Because the outer tube  34  prevents rotation of the nut  40 , rotation of the drive shaft  42  causes the nut  40  to translate vertically. The drive shaft  42  further includes a lengthwise inner passage  41  and key ways  43  running vertically lengthwise into the inner passage  41 . The inner passage  41  is preferably cylindrical to reduce manufacturing costs, but may have other cross-sections. 
     A side view of the nut  40 , according to the present invention, of the center column assembly  30  of the juicer  10  is shown in  FIG. 11A , and a top view of the nut  40  is shown in  FIG. 11B . The nut  40  includes a threaded interior  47  for cooperation with threads  45  on the drive shaft  42  (see  FIG. 10A ) and external notches  44  and external lands  46  on the exterior of the nut. The lands  46  center the nut  40  in the inner passage  41  of the drive shaft  42  and the notches  44  prevent the nut  40  from rotating inside the outer column  34 . Only one notch  44  is required and in another embodiment, the nut may include a projecting key for cooperation with a key way inside the outer column  34 . 
     A side view of the driven shaft  38 , according to the present invention, of the center column assembly  30  of the juicer  10  is shown in  FIG. 12A , a bottom view of the driven shaft  38  is shown in  FIG. 12B , and a top view of the driven shaft  38  is shown in  FIG. 12C . The driven shaft includes two keys  48  for cooperation with the key ways  43  in the drive shaft  42 , causing the driven shaft  38  to rotate with the drive shaft  42  but allowing the driven shaft  38  to translate vertically with respect to the drive shaft  42 . The keys  48  of the driven shaft  38  rest on the nut  40  to vertically couple the driven shaft  38  to the drive shaft  42 . The driven shaft  38  further includes a cylindrical body  50  and a hexagonal nose  54  at an upper end for engaging the lift tube  32 . 
     A side view of a lift tube  32 , according to the present invention, of the center column assembly  30  of the juicer  10  is shown in  FIG. 13A , a bottom view of the lift tube  32  is shown in  FIG. 13B , a top view of the lift tube  32  is shown in  FIG. 13C , and a cross-sectional view of the lift tube  32  taken along line  14 - 14  of  FIG. 13A  is shown in  FIG. 14 . The lift tube  32  has a hexagonal exterior  6 , a round base flange  58 , and a hexagonal recess  56  in the base for cooperation with the nose  54  of the driven shaft  38  (see  FIG. 12A ). The lift tube is lifted and rotated by the driven shaft  38  and lifts and rotates the juicing cone  26  (see  FIG. 5C ). 
     A second embodiment of a center column assembly  70 , according to the present invention, of the juicer  10 , is shown in  FIG. 15 . The center column assembly  70  includes an inner tube  74 , a second outer tube  34 ′, and a hexagonal driven shaft  72 . The second outer tube  34 ′ is similar to the outer tube  34 , but does not include the ceiling  37 , allowing the inner tube  74  to be inserted into the top of the outer tube  34 ′ and have an outer diameter sliding into the interior of the outer tube  34 ′. The exterior of the inner tube  74  includes a notch  76  running the length of the inner tube  74  to engage the vertical rail  39  of the outer tube  34 ′ to allow the inner tube  74  to translate vertically within the outer tube  34 ′, but to cause the inner tube  74  to rotate with the outer tube  34 ′. The hexagonal driven shaft  72  engages the juicing cone  26  to lift and rotate the juicing cone  26  (see  FIG. 5C ). The center column assembly  70  is otherwise similar to the center column assembly  30 . 
     A second fruit holder  24 ′ with an adjustable seat  80  is shown in  FIG. 16 . 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. 17A  and in a high torque position in  FIG. 17B . 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. 
     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.