Low cost quick insert citrus strainer tube

A low-cost strainer tube which can be quickly replaced in a citrus fruit juice extractor. The tube includes a hollow perforated sleeve which can be quickly inserted into a hollow body member and can be quickly removed. The sleeve has a plurality of groups of radial perforations which align with corresponding radial holes in the body member to allow juice to flow from an inside of the sleeve to an outside of the body member. To the amount of pulp which flows through the perforations it is necessary to remove only the sleeve and substitute another sleeve with different size perforations.

BACKGROUND OF THE INVENTION 
The present invention generally relates to apparatus for extracting juice 
from fruit, and more particularly, to an improved low-cost strainer tube 
for use in juice extractors. 
The complete commercial processing of citrus fruit to obtain juice 
therefrom today includes the dejuicing and discharging of the pulp and 
internal membranes of the fruit, the breaking up and ejecting of the peel, 
the extracting and collecting of the peeled oil, and the separate 
extracting and collecting of the fruit juice. 
In a typical extractor a whole unpeeled citrus fruit is placed between two 
cups, each of which is formed by a plurality of circumferentially spaced 
fingers and one of which is provided with a passage to allow discharge of 
juice and pulp from the fruit. The fingers of the upper and lower cup are 
arranged in an interdigitating relationship so that as cups are brought 
together, the cavity between the cups is progressively reduced to squeeze 
juice from fruit within the cavity. The peel of the fruit is shredded and 
ejected through an annular opening adjacent to the upper central portion 
of the upper cup. The juice-bearing material of the fruit is forced 
downwardly through the passage in the lower cup and into a perforated 
strainer tube which communicates with the lower cup. As the fruit is 
squeezed between the cups, an orifice tube is forced upwardly within the 
strainer tube to exert pressure on the juice-bearing material within the 
strainer tube to express the raw juice through the perforations therein. 
The raw juice expressed through the strainer tube is collected within a 
sump or manifold which extends transversely of the machine through the 
lower cup assemblies. 
The movement of the orifice tube within the strainer tube and squeezing of 
juice through the perforations cause wearing of the strainer tube which is 
expensive to replace both because of the cost of the manufacturing of the 
tube and of the time required in replacing the tube. 
SUMMARY OF THE INVENTION 
The present invention discloses a strainer tube which is relatively 
inexpensive to manufacture and can be quickly replaced. The strainer tube 
is made in two parts with an inexpensive hollow perforated sleeve being 
mounted inside a generally cylindrical body member having an axially 
extending bore. The body member includes a plurality of holes which extend 
radially outward from the actual bore. The hollow sleeve includes a 
plurality of groups of perforations with each of the groups of 
perforations being positioned adjacent to a corresponding one of the body 
member holes so juice can move axially outward from an end side of the 
hollow sleeve through the perforations and through the body member holes 
to an outer portion of the body member.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
A portion of a citrus juice extractor 10 in which the present invention can 
be used is shown in FIG. 1. Extractor 10 includes a bed plate 11 having a 
lower cup 12 rigidly connected thereto by a plurality of stud bolts 16. An 
upper cup assembly 17 is mounted on the lower end of a drive rod 18 above 
cup 12 so that the upper cup can be moved directly downwardly to engage 
fruit disposed in the lower cup. The drive rod 18 is secured at its upper 
end to a drive mechanism (not shown) which provides vertical reciprocal 
movement. A plurality of upper cup fingers 22 are mounted on the lower end 
of drive rod 18 to form an interdigitating fruit cup with a plurality of 
lower cup fingers 23. A strainer tube 24 of the present invention is 
vertically secured to bed plate 11 by a nut 28 which is threaded on a 
lower threaded end portion 29 of tube 24. An upper end of strainer tube 24 
is rigidly mounted to an annular cutter 30 which, in turn, is fixed to bed 
plate 11. A tubular plunger 34 slides within strainer tube 24 powered by a 
drive assembly 35 attached to the lower end of plunger 34. 
After a fruit F is deposited in the lower cup 12 the associated upper cup 
and assembly 17 is moved downwardly to engage the fruit. At the same time 
plunger 34 below the cup is raised within strainer tube 24 in timed 
relationship with the lowering of the upper cup assembly. 
The lower cup 12 comprises a plurality of equally spaced, upstanding 
fingers 23 that extend upwardly from a hub portion 36. The upper cup and 
the upper cup assembly 17 is comprised of similar equally spaced 
downwardly depending fingers 22. The fingers 22 of the upper cup are 
arranged in an interdigitating relationship with the fingers 23 of the 
lower cup so when the cup assemblies are brought together, the lower ends 
of the upper fingers and the upper ends of the lower fingers are received 
in spaces between the fingers to form a generally spherical pocket in the 
center of the cup assemblies to receive the fruit F. The pocket is then 
progressively contracted as the cup assemblies are moved together. 
Generally, the contracting of the cavity between a pair of upper and lower 
cups first causes a plug PL (FIG. 1) to be cut from the underside of the 
fruit, and thereafter the cavity is reduced to the point where all of the 
juice and other solid internal portions IP of the fruit are forced into 
the strainer tube 24. Such solid internal portions IP included membranes, 
juice sacs, seeds, etc. Simultaneously therewith, plunger tube 34 is moved 
upwardly. A series of plugs PL and internal fruit portions IP removed from 
the previously processed fruits are engaged in the bore of the plunger, 
such plugs and materials prevent the juice within strainer tube 24 from 
egressing through the passage in the tubular plunger. As the plunger moves 
upwardly, juice and internal portions that are forced into the strainer 
tube by the compressing force of the cups upon the fruit will be placed 
under increasing pressure to force the juice and some minute particle 
solid material, such as juice sacs or pieces of membranes, outward through 
apertures in the strainer tube. The discharged juice and minute solid 
material is collected within a manifold 40 and discharged through a 
conduit 41. 
Details of strainer tube 24 of the present invention are disclosed in FIGS. 
2-4. Tube 24 includes a hollow cylindrical body member 42 having an axial 
bore 46 extending through the length of body member 42. A plurality of 
holes 47 extend radially outward from bore 46 to an outer portion 48 of 
body member 42. An outwardly projecting flange 53 and nut 28 on the 
threaded end portion 29 (FIG. 1) secure body member 42 to a bottom wall 54 
(FIG. 1) of manifold 40. 
A hollow perforated sleeve 55 is mounted inside bore 46 of body member 42 
with a lower end 55a against a shoulder 59 in body member 42. A plurality 
of groups 60 of perforations 61 are formed in the wall of hollow sleeve 55 
with each of groups 60 being mounted adjacent to a corresponding one of 
the holes 47 in body member 42 (FIGS. 2, 3). This allows juice to flow 
from an inside 55b of hollow sleeve 55 out through perforations 61 and 
through hole 47 to the outside of body member 42. A slot 66 (FIGS. 2, 4) 
in the lower end portion of hollow sleeve 55 fits around a pin 67 mounted 
in a bore 68 in the lower end portion of body member 42 to insure that 
each of the perforation groups 60 are properly aligned with a 
corresponding hole 47. Annular cutter 30 (FIGS. 1, 2) is positioned about 
upper end portions 42c, 55c of body member 42 and sleeve 55 to secure 
hollow screen 55 securely in place in juice extractor 10. 
The cost of manufacture of hollow sleeve 55 is relatively low because only 
the areas adjacent to holes 47 of body member 42 have perforations 61 
formed in sleeve 55. The cost of making sleeve 55 is also relatively low 
because the walls can be fairly thin as the walls of body member 42 
reinforces sleeve 55. Changing sleeves 55, because of wear or because 
different sized perforations are desired, is relatively easy. Cutter 30 is 
removed and sleeve 55 is pushed upward out of body member 2 and another 
sleeve is pushed downward into place It is not necessary to remove body 
member 42 from the extractor. 
Thus, the cost of manufacture and cost of changing sleeves is much lower 
than the cost of similar operations in a single-piece type of strainer 
tube. 
Although the best mode contemplated for carrying out the present invention 
has been herein shown and described, it will be apparent that modification 
and variation may be made without departing from what is regarded to be 
the subject matter of the invention.