Abstrict A grape crusher and de-stemmer comprising a drum (5) having a spiral
rotor blade (8) eccentrically mounted in the drum to have a greater
clearance at the top and at the bottom. The drum is perforated with
perforations (1819) and means are provided for rotating the rotor
at high speed to remove the berries from the stalks and to split
the berries so that the juice may be extracted.
Claims The claims defining the invention are as follows:
1. A grape handling and de-stemmer apparatus comprising a perforated
generally horizontal stationary drum, an inlet at one end of the
drum, an outlet at the opposite end, a driven shaft eccentrically
mounted within said drum, blades mounted on said driven shaft to
provide a clearance between the blades and the internal surface
of the drum to move grapes from said inlet to said outlet, the clearance
between said blades and said drum being greater at the top than
the bottom, and means to rotate said shaft at a speed to move the
grapes in range of about 5 meters per second to about 20 meters
per second circumferential speed over the internal surface of the
drum while removing the grapes from the stalks and opening the grapes
for the juice to be extracted by rolling said grapes between the
blades and the internal surface of the drum in the decreasing clearance
at the bottom of the drum to split said grapes, the grapes falling
from the blades in the increased clearance toward the top of the
drum.
2. A grape handling and de-stemmer apparatus as defined in claim
1 characterized by a pair of blades supported on arms mounted on
said shaft, said blades having a flat spiral in the range of one
turn per 0.5 meter to one turn in 2 meters.
3. The apparatus as defined in claim 2 characterized in that the
spiral is a continuous spiral.
4. The apparatus as defined in claim 1 characterized in that the
spiral is formed of a number of sections spaced circumferentially
and longitudinally of each other.
5. The apparatus as defined in claim 1 characterized in that the
inlet is tangential to the drum in the direction of rotation of
the spiral blades.
6. The apparatus as defined in claim 1 characterized in that the
drive means is a variable speed drive means.
7. A grape handling and de-stemmer apparatus comprising a perforated
generally horizontal stationary drum, a tangential inlet at one
end of the drum, an outlet at the opposite end of the drum, a driven
shaft eccentrically mounted within said drum, a pair of blades supported
on arms mounted on said driven shaft, said blades having a clearance
from the internal surface of the drum, said blades having a flat
spiral to move the grapes from the inlet to the outlet end, and
means for rotating said driven shaft at a peripheral speed to maintain
the grapes by centrifugal force on the wall of the drum up to near
the top of the drum, the driven shaft being mounted to give the
blades a greater clearance at the top of the drum than at the bottom
of the drum, the clearance at the bottom being sufficient to give
a rolling action to the grapes as they approach the lesser clearance
to crack and open the grapes without crushing, the greater clearance
at the top freeing the grapes from the blades, the action of the
blades opening the grapes and removing the stalks therefrom.
Description This invention relates to the crushing of grapes, and more particularly
to a crusher adapted to rupture the skins of the grapes in a simple
manner.
BACKGROUND OF THE INVENTION
Conventionally grape crushers include the step of passing the bunches
of grapes through at least a pair of grooved spaced rollers so that
the grape berries are crushed to allow the juices to be extracted
therefrom by a pressing operation.
These rollers through which the grapes pass must crush the grapes
and also tend to damage the stems and stalks, and often tend to
break these into smaller pieces.
U.S. Pat. No. 3034423 by Albert Demoisy discloses a continuous
rotary press for extracting liquid from fragile products (for example
fruits) where a rotor operates within a perforated housing, the
rotor being divided into a plurality of compartments and carrying
rollers and endless track members to press the material retained
by the perforated housing.
R. G. Lohre et al in U.S. Pat. No. 2682832 discloses an apparatus
for removal of juice from citrus fruit, with the rotor being mounted
eccentrically within the rotatable outer casing so that the fruit
is compressed to squeeze the juice therefrom.
U.S. Pat. No. 3011430 discloses an orange juice extractor wherein
the fruit is subjected to a gradually increasing pressure, to squeeze
the juice from the orange, the extractor including a rotor acting
in conjunction with a surrounding drum.
U.S. Pat. No. 292524 by Wilson and U.S. Pat. No. 2119972 by
Steinbiss each disclose apparatus having a spiral or similarly shaped
rotor to move the material, the spiral body increasing in diameter
to produce an increasing pressure.
It is an object of this invention to provide a grape crusher in
which the grape berries are crushed, split or opened in a simple
manner to allow the juice to be extracted therefrom.
It is a further object to provide a grape crusher in which there
is a ready separation of the stalks and stems from the crushed berries
and pips with there being a minimum of damage to the skins themselves
and also to the stems and stalks.
BRIEF STATEMENT OF THE INVENTION
Thus there is provided according to this invention a grape crusher
comprising spiral means to transport the grapes through a treating
zone, means for rotating the spiral at a speed such that the grapes
are forced by centrifugal force to the wall of the crusher so that
the action of the spiral on the grapes adjacent the wall causes
the berries to be split and opened.
Throughout the specification while reference is made to the invention
as a grape crusher, it is to be realised that the term crusher is
not used in the usual sense of pressure being applied between rollers
or the like, that is merely used to refer to the action of breaking
the skins of the grapes to open up the grapes so that the juice
can be extracted.
In a preferred form the crusher is a cylindrical drum, a spiral
being mounted within the drum.
The spiral in its preferred form can comprise a two bladed spiral
having a large pitch, the spiral blades being mounted on radial
arms.
The cylindrical drum is preferably formed of metal and is provided
with a plurality of apertures. Adjacent the inlet end these apertures
are of relatively small size, and then increase in diameter toward
the outlet end.
It is to be noted that in the preferred form the spiral is not
mounted centrally within the cylindrical drum, but is so positioned
that it has a small clearance at the bottom while at the top there
is a larger clearance.
The drum is provided with an inlet chamber or hopper, this being
offset from the central axis of the drum and is thus positioned
to one side of the vertical diameter of the drum and on that side
where the spiral blades pass downwardly so that there is little
or no tendency for any of the grapes being fed in to fly up out
of the drum.
Means are provided to drive the spiral at a relatively high speed,
this being preferably by an electric motor or the like, either mounted
on or adjacent to the cylindrical drum. It has been found that with
the above clearances given and the pitch as above stated that by
rotating the spirals at a speed of 700 revolutions per minute or
in other words approximately 11 meters per second circumferential
speed, this speed is sufficient to lift and throw the grapes against
the wall of the drum and due to increasing and decreasing clearance
as the spiral blades move around the wall of the drum the grape
berries are split and opened and removed from the stalks.
The stalks in this way are not crushed or bruised to any appreciable
extent and the blades of the spiral as they pass over the openings
in the drum pass the split berries, skins and pips through these
openings to be collected for later pressing.
A large quantity of juice is extracted from the grapes in the initial
opening and crushing of the grapes, and this juice is collected
in the initial or earlier part of the crushing action, this juice
collected being exceptionally free from any skins, pips, stems or
twigs or the like, and as the skins themselves are not crushed the
juice extracted is the free juice within the grape itself and is
thus a highly desirable juice which is obtained in this manner.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevation of the crusher according to the invention
FIG. 2 is an end elevation thereof and
FIG. 3 is a view of the spiral blades and the drum portion being
broken away for clarity
DESCRIPTION OF THE PREFERRED EMBODIMENT
The crusher and the stemmer 1 comprises a drum assembly 2 mounted
on a frame base 3 having a plurality of legs 4. The drum assembly
2 includes a drum 5 having an inlet 6 and outlet 7.
A spiral rotor 8 is fixed to a shaft 9 mounted in bearings 10 affixed
to end plates 11 on the ends of the drum 5. The spiral rotor 8 is
driven by a feed belt drive from a variable speed geared motor 13
having a variable speed adjusting hand wheel 14.
Beneath the drum 5 there is supported on the frame 3 a drain tank
to collect the juice extracted or removed from the grapes passing
through the drum.
The rotor blade 8 comprises a pair of spiral blades 15 mounted
on blade arms 16 attached to the shaft 9 each blade having a limited
depth 17.
The blade arms 16 are plates supporting the blades at a distance
from the shaft 9.
The drum 5 is provided with a plurality of openings, these varying
as desired. However in a preferred form more holes 18 are provided
adjacent the inlet opening 6 and also small holes 19. Spaced further
along the drum the holes 20 are large in diameter.
As shown and in accordance with the invention, the shaft 9 is not
situated centrally of the drum, but is displaced slightly downwardly
so that the clearance 21 at the top is greater than the clearance
22 at the bottom. In this way as the grapes move from the area of
greater clearance to the lesser clearance they are split and opened
by the action of the blade on the drum thus opening the berry and
allowing the juice to escape.
In a typical example of a grape crusher and de-stemmer capable
of handling ten tonnes of grapes per hour, the rotor blade could
be 1632 millimeters in length and in this length each blade turns
through 460 degrees, that is one and one quarter turns so that the
angle of the blade to the axis of the blade is at a relatively shallow
angle with the diameter of the blade being 240 millimeters.
The diameter of the drum could be about 286 millimeters so that
the rotor by being offset then gives a clearance at the bottom of
6 to 10 millimeters with corresponding larger clearance at the top.
The rotor is adapted to run at a speed of approximately 11 meters
per second circumferential speed and this lifts and maintains the
grapes against the internal surface of the drum by a centrifugal
force and due to the variation in clearance, as the grapes move
toward the lower area they are effectively split and opened by the
action of the rotor blades on the interior of the drum.
This splitting allows the juice to come free of the berries. The
smaller holes at the inlet end of the drum can be in the vicinity
of 20 millimeters in diameter while the holes in the remainder of
the drum can be in the order of 28 millimeters.
In a preferred form adjacent the 20 millimeter holes there are
provided a plurality of slots around the portion of the drum adjacent
the inlet opening, these slots being 20 millimeters long and 8 millimeters
wide.
It has been found that with the arrangement of the slots and holes
that the juices and berries can pass through these holes, but that
the stalks and stems are retained for discharge out through the
outlet end of the drum so that the berries can then be further processed
by pressing to extract the juice therefrom. As the berries have
been removed from these stalks and split and opened without any
undue damage to the skins themselves then a pure juice is extracted
without any contaminants from the skin and or stalks.
Although in the preferred form dimensions are given as an example
only of the invention, it is to be realised that the production
unit will be much larger in diameter and of greater length, thus
being able to handle greater quantities of grapes.
It will be realised that in this instance where the crusher is
made of differing sizes, that the speed with which the spiral must
be rotated could well be varied and as the diameter is increased
the number of revolutions per minute would be decreased to give
a peripheral speed similar to the above.
Also it is to be realised that with the larger units the speed
may have to be varied or increased to cause the bunches of grapes
to be held by centrifugal force against the walls, or can be varied
so that the grapes may tend to tumble or fall during the operation.
The large pitch of the spiral will gradually move the grapes through
the crusher, these spirals thus acting as beaters having a slight
inclination to move the grapes and must through the crusher. The
pitch of the spirals could vary between one turn for 0.5 meters
to one in 2 meters.
It will realised that while there is disclosed the continuous spiral,
that the spiral could be comprised of a number of individual paddles
or beaters each inclined at an angle, these beating and pressing
the grapes against the outer wall in order to remove the berries
from the stems and to split the skins to allow the subsequent extraction
of the juice.
Thus it will realised that various modifications can be made to
the above invention relating to the various sizes and dimensions,
as long as the basic concept of a relatively high velocity is achieved
in order to produce the desired effect with the paddles, beaters
or other blades or the spiral progressively moving the grapes through
the unit.
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