SpencCracker, an apparatus for shucking pecans

An apparatus for shucking pecans having a stator, which is a trapezoidal front plate with a pair of adjoining tapered side-walls with longitudinal edges, a mounting bracket for immobilizing the stator, and a chute which is a reservoir for the pecans, where said stator is axially connected to a rotor, which is a circular back plate that pivots at the centroid of the front plate; the combination of the back plate and the front plate forming a chamber that is narrow at the bottom, wherein the pecans are cracked as the rotor is rocked back and forth through an arc, where the rocking action forces the pecans into compression and then in the reverse rock into relief, where the shell separates from the kernel.

BACKGROUND 
The invention is an apparatus for cracking nuts, and more particularly an 
apparatus for shucking pecans that produces whole halves at a very high 
percentage. 
The prior art of shucking nuts, and in particular shucking pecans using 
automated or partially automated cracking devices, reads on basically two 
types of nut crackers, wherein a type is distinguished in terms of how 
compressive forces are created and applied to the shell of the nut. In the 
first type, compressive forces are applied simultaneously to substantially 
the entire surface of the shell, and in the second type the compressive 
forces are applied progressively, and principally perpendicularly to the 
longitudinal walls of the shell. The first type of nut cracker usually 
creates the compressive forces through an collection of rods which in-cage 
the nut and crush the shell. The second type, which is better suited for 
automation in that this type usually requires fewer active elements, 
conveys the nut into a progressively narrower nip which therein causes the 
longitudinal walls of the shell to be crushed. Illustrative of the first 
type of nut cracker is Miller' U.S. Pat No. 3,965,810 patent. Miller's nut 
cracker is comprised of a plurality of rods mounted distally in a pair of 
handled circular plates having a center aperture. When the handles are 
twisted, the rods constrict radially, and therein apply leveraged 
compressive force to the shell of a nut positioned within the rods. An 
illustration of the second type of nut cracker is Joyama' U.S. Pat No. 
4,819,331 invention. Joyama's automated nut cracker looks similar to a 
centrifugal pump, wherein the gears act to crush a pair of opposing 
longitudinal walls of the shell, while pumping the nut through the 
progressively narrower constriction. 
Some of the prior art has elements of both types of nut crackers. 
Daugherty's pecan shucker' U.S. Pat No. 5,544,574, forces the nut through 
a multitude of rollers using an axial longitudinal rod, wherein the 
rollers apply circumferential compressive forces to the entering end 
portion of the shell of the nut. The forces are similar to the first type 
of cracker, in that they are circumferential, however, similar to the 
second type in that the compressive forces are acting on only a portion of 
the nut. In Packwood's nut cracking machine' U.S. Pat No. 4,073,032, the 
rollers are driven, and there is no need for a rod, however the nut will 
assume the same orientation, such that an end portion of the nut will be 
compressed circumverentially. Unanimous to all the prior art is that the 
nut is always under compression while in the nut cracker, therein not 
enabling a time for the nut to reorientate. These two factors, constant 
compression and no reorientation limit the mechanisms by which the shell 
can separate from the kernel. 
The success of the shucking process is generally gauged on the efficiency 
with which the shell is relieved from the nut without damaging the kernel, 
and in the case with pecans, the percentage of whole halves has 
traditionally been the benchmark. 
It has been observed that while the first type of nut cracker produces a 
relatively good percentage of whole halves, the yield is not as high as 
anticipated. A possible explanation for the lowered efficiency is that 
while the compressive forces are uniform, their combined effect produces a 
more rigid shell, because the elongated round shell is under tension 
inward, and the higher rigidity results in a more explosive type cracking 
action. 
The second type of nut cracker applies force principally to just the sides 
of the shell, consequently the kernel frequently breaks apart leaving 
portions of the kernel in the parabolic ends of the pecan, as the nut is 
never reorientated in the nip, and compression is therefore never applied 
to the ends of the nut. This second type of nut cracker can have very high 
through-puts, but often lower efficiency in terms of percentage of whole 
pecan halves 
An improved apparatus for cracking nuts, and particularly pecans, would 
have a mechanical action that would sequentially apply just enough 
compressive force to a section of the shell so as to crack the shell 
without damaging the kernel, and continue to repeat the mechanical action 
until a sufficient number of sections of the shell had been cracked so as 
to liberate the kernel from the shell, and in so doing produce a very high 
percentage of whole halves. It necessarily follows that said mechanical 
action would require either the reorientation of the nut after cracking a 
section, or reorientation of the spatial axis of the compressive force, 
relative to the nut 
SUMMARY OF THE INVENTION 
The invention is an apparatus for shucking pecans, wherein through 
relatively uncomplicated mechanical means, the invention, produces a 
mechanical action that shucks pecans, where the resulting kernels are 
produced with a very high percentage of whole halves. 
It is a first object of the instant invention to produce a mechanical 
action that allows the nuts to be compressed, and then decompressed and 
reoriented, in a repeating fashion, until substantially all of the shell 
has been cracked and the shell is relieved from the kernel. The mechanical 
action is a series of cyclic repetitive movements, which, depending on the 
location within a chamber, acts on a portion of the nuts to compress a 
section of the shell of the nut, while another location of the chamber, 
simultaneously acts on a different portion of nuts to decompress and 
reorient the nuts. In the succeeding half cycle the action is reversed. 
The series of cyclic repetitive movements is complete when the shell is 
relieved from the kernel and the nut is sufficiently diminutive to exit 
the nut cracker. 
It is a second object of the instant invention that the apparatus be 
relatively inexpensive to manufacture, and that the materials of 
construction be readily available. Components were selected with 
consideration being given to not only their functional utility, but also 
with an eye for the ultimate cost of manufacture, as the instant invention 
is intended to be sold to the consuming public, as well as professional 
food processors. A somewhat serendipitous balance was achieved in the 
inventive process through the selection of existing rugged hardware 
already in wide distribution, and the functional adeptness of the 
components which has resulted in a new type of nut cracker that is not 
only extremely efficient (in the context of whole halves), but also 
relatively uncomplicated to manufacture. 
The invention has a stator, a rotor, and a connecting bearing element that 
fixes the relative position of the stator and the rotor and enables the 
rotor to rotate. The stator is mounted to an immobilizing structure, and 
the rotor pivots through an arc substantially axial to the stator. The 
stator has a front plate, and the rotor has a back plate. The front plate 
is a substantially vertically orientated trapezoidal shaped stiff plate 
with a pair of adjoining tapered side-walls, wherein the upper edge of the 
top of the plate there is cut out a sectional arc. Attached, near a center 
loci of the front plate, or a centroid, there is a fastening means for a 
connecting bearing element which attaches the back plate to the front 
plate. The fastening means at the centroid is usually just an aperture, 
however, there can also be other devices, such as a bearing. The 
connecting bearing element enables the back plate to rotate relatively 
freely, and provides axial rigidity that keeps the rotation substantially 
free of wobble, even when perturbed by uneven distortional forces as a 
consequence of applying compression to a pecan. A trapezoidal face on the 
front plate is tilted slightly away from the back plate such that the 
front plate and the back plate are angularly offset from each other, when 
viewed from the side. The space separating the front plate from the back 
plate is wider at the top than at the bottom, so that a chamber, formed by 
the attached front and back plate, is wider at an entrance than at an exit 
at the bottom of the chamber. The adjoining side-walls are appropriately 
tapered along their longitudinal edges to allow for the angular offset of 
the two plates, such that cracked nuts are retained by the sidewalls, and 
yet the back plate can rotate in either direction with minimal resistance 
while the front plate is held stationary. The space separating the front 
plate from the back plate can be fine tuned by adjusting the connecting 
bearing element, which generally consists of a threaded fastening 
component(s). The front plate is fitted with a mounting bracket for 
securing the apparatus to a table or other suitable immobilizing 
structure. Both the front plate and the back plate have a textured 
surface. A preferred material is a heavy gauge Checker Plate. The back 
plate is fitted with a driving element, such that when powered, the entire 
back plate is rotated back and forth through an arc in a reciprocating 
manner. For manual operation a pipe can serve as a driving element. 
Mechanized versions would employ some type of cam arrangement. The 
entrance of the chamber is suitably wide enough to accommodate the feeding 
of pecans and other nuts. The entrance is fitted with a chute, which 
extends outward from the sectional arc of the upper edge, wherein the 
chute serves as a reservoir for feeding the nuts into the apparatus. The 
exit of the chamber is sufficiently narrow as to prevent uncracked nuts 
from escaping. 
To better understand the mechanism of the invention, imagine a 
perpendicular plane vertically bisecting the chamber created by the front 
and back plates. The invention works as follows. The chute is loaded with 
nuts, and then the apparatus is activated. Activation causes the driving 
element to rock the back plate to-and-fro through a 30 to 120 degree arc. 
A preferred degree arc is 40-90, and the more preferred degree arc is 
45-60. The rocking action, incidentally, jostles the nuts, therein 
imparting vibrational energy to the nuts so that they slide down the chute 
into the entrance of the chamber. In the chamber, the nuts have a brief 
period in which they orient based on their shape in relation to the 
progressively narrower dimensions within the chamber. The angular motion 
of the back plate creates vectoral forces on the nut that, depending on 
the location of the nut within the chamber, tend to move the nut deeper 
into the chamber or to an position having reduced compressive action. 
Arbitrarily picking a starting point for the first half cycle, assume that 
the back plate moves from the left to the right. Nuts in the chamber 
located at the right outer-most side of the chamber will be conveyed the 
furthest distance downward through the chamber as the back plate rotates 
right, because the nuts are furthest from the axis, and the motion tends 
to convey them downward deeper into the chamber. Since the chamber gets 
progressively narrower from top to bottom then the compressive cracking 
forces are highest on a nut near a periphery of the back plate. Nuts 
located further to the left, closer to the perpendicular plane, will tend 
to be conveyed laterally, as the angular movement of the back plate to the 
right will tend to move the nuts longitudinally to the right. Also, nuts 
already under compression can shift toward the axis to relieve some of the 
compressive forces during the rotation. In contrast, nuts in the left most 
portion of the chamber, will be conveyed the furthest distance upward 
through the chamber, and to a region of minimal compression. Under relief 
of compression, there is then ample room for the kernel to separate from 
the shell. The nuts just above or below the axis of rotation are conveyed 
longitudinally either to the right or left, depending on their relative 
orientation. This movement can enable the nut to reorient if further 
cracking is required. In the second half of the cycle the back plate is 
moved left, back through the center position and then all the way left. 
The reciprocal action reverses which nuts are under compression and which 
are in relief Below the axis, the trapezoidal shape of the tapered front 
plate keeps the nuts closer to the perpendicular plane of the apparatus, 
therefore most of the movement in the narrower regions of the chamber, is 
longitudinal, and the resulting compressive forces are more subtle and 
less likely to damage the kernel. The combination of compression and 
relief results in a nut cracker that produces whole halves at a very high 
percentage. In summary the shucking steps are iterative, and consists of 
the following: 
1. Moving a whole pecan(s) or a partially shucked pecan(s) to a location in 
the apparatus wherein compression is high, therein applying sufficient 
compression to a partial shell wall to affect cracking; 
2. Removing said whole pecan(s) or said partially shucked pecan(s) to 
another location in the apparatus wherein compression is low, therein 
creating sufficient space for the partial shell wall to separate from the 
kernel, and wherein the step of said removing incidentally generates 
sufficient vibrational energy to enable the pecan to reorient in the 
apparatus; 
3. Repeating the first two steps until the shucking process has reduced the 
pecan to a size sufficiently diminutive to exit the apparatus. 
It is anticipated that the instant invention can readily be mechanized and 
further automated. The modifications would not materially benefit nor 
change the underlying art of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
FIG. 1 is a perspective drawing of the invention 1. The invention is hand 
operated and is called the SpencCracker. There are three major components, 
the stator 2, the rotor 3, and the connecting bearing element 4. The 
stator 2 has a front plate 12, and the rotor 3 has a back plate 11. The 
back plate 11 is fitted with a handle 13 for rocking the back plate 11 
through an arc. The arc is typically around plus or minus 30 degrees off 
the vertical, for a total of 60 degrees from left to right, and then 60 
degrees from right to left, and so on. In operation the handle 13 would be 
rocked until all the pecans are shucked. The back plate 11 and the front 
plate 12 are fabricated with heavy gauge Checker Plate, which is a steel 
sheet typically utilized in the construction of catwalks, and other 
industrial applications. The steel sheet has a cross-hatched or checkered 
pattern stamped into it to impart a roughened texture to the steel sheet. 
The checkered pattern reduces slippage. The back plate 11 and the front 
plate 12 are positioned such that the checkered pattern of the front plate 
12 faces the checkered pattern of the back plate 11 to maximize the 
gripping characteristics of the two plates. The back plate 11 is connected 
to the front plate 12 with the connecting bearing element 4, which 
consists of a bolt 15, which is welded to the back plate 11, a sleeve 18, 
a washer 17, and a pair of suitable nuts 16. FIG. 4 and FIG. 5 show the 
bolt 15, of a disassembled connecting bearing element. The bolt 15 
projects perpendicularly from the back plate. The bolt 15 is tap welded to 
the side of the back plate 11 which is out of view. The bolt 15 projects 
through an aperture 31 in the front plate 12. The aperture 31 is shown in 
FIG. 5. Note the taper in the side-wall 30 from the top of the plate to 
the bottom substantially determines the depth of the chamber. The 
connecting bearing element 4 enables the back plate to rotate relatively 
freely, and provides axial rigidity that keeps the rotation substantially 
free of wobble or flex, even when perturbed by uneven distortional forces 
as a consequence of applying compression to a pecan. Pecans 20 are loaded 
into the chute 19 prior and during shucking. The chute 19 serves as a 
reservoir for the pecans 20, and also funnels the pecans into the pecan 
shucker 1. The chute 19 is welded to the sectional arc 26 of the front 
plate 12. Both of the side-walls 27 on the front plate can also be viewed 
in FIG. 5. The pecan shucker is mounted on an immobilizing surface when in 
use. In FIG. 1 a bracket 14 is used to mount the front plate 12 to a table 
22. The bracket 14 can be viewed from the side in FIG. 2. Referring again 
to FIG. 2, note that the side-walls 27 and the trapezoidal face 28 of the 
front plate, in combination with the back plate 11, form the chamber 23. 
The entrance 24 to the chamber 23 and the exit 25 are marked accordingly. 
The chamber 23 is where the pecans are shucked. The space in the chamber 
23, as measured from the front plate 12 and the back plate 11, can be 
adjusted slightly by narrowing the gap 29 between the back plate and the 
longitudinal edge of a side-wall 30. This adjustment will periodically be 
required to accommodate pecans having atypical dimensions. The adjustment 
can facilely be made by appropriately tightening or loosening the nuts 16 
on the connecting bearing element 4. The front plate 12 is angled relative 
to the back plate 11 such that the space in the chamber 23 is much tighter 
near the exit 25, than at the entrance 24. Dimensions of a prototypical 
invention are side-walls 1.5 inches wide at the entrance, and tapering to 
0.5 inches at the exit. The trapezoidal face is 8.25 inches at the top, 
and 5 inches at the bottom. The diameter of the back plate is 10 inches, 
with a 4 inch handle. The bolt of the connecting bearing element is 0.75 
inches in diameter and 6 inches long. The Checker Plate is approximately 
0.125 inches thick. 
FIG. 3-1, FIG. 3-2, and FIG. 3--3 sequentially take the reader through the 
action of the instant invention. The action is angular, with the pivot 
point being the aperture 31 through which the bolt 15 of the connecting 
bearing element 4 passes. One of the checkers 32 has been marked with 
cross-hatching to more clearly describe the action on both sides of the 
perpendicular plane. A perpendicular plane is indicated by sectional lines 
3-1, 3-2 and 3--3 respectively. From observing FIG. 1 to FIG. 3, the pecan 
20 is forced further down into the chamber as the handle is moved from the 
left to the right. The pecan 20 would be cracked with action. This 
movement was described in the first step of the shucking process 
previously elaborated on. On the opposite side of the perpendicular plane, 
the cross-hatched checker 32 has shifted upward, removed to a position 
where there is sufficient room for a portion of the shell wall of the 
pecan to separate from the kernel. The action of the cross-hatched checker 
corresponds to the second step in the shucking process. In the succeeding 
iterative operation the handle would be moved from the right to the left, 
and the actions of the pecan and the cross-hatched checker would be 
reversed. Ultimately all of the shell wall is removed, and the size the 
processed component parts would be sufficiently diminutive to exit the 
apparatus. This step corresponds to the third step in the shucking 
process.