Note: Descriptions are shown in the official language in which they were submitted.
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VENTILATION SYSTEM TO VENTILATING PARTICULATE MATERIALS
DISPOSED IN A STORAGE BIN
The present invention relates to ventilation of particulate materials
disposed in a storage bin, and more particularly to a ventilation system using
naturally occurring convection.
BACKGROUND OF THE INVENTION
After harvest grain such as, for example, wheat, rye, barley, canola,
soybeans, is stored in storage bins -- on site at a farm or in large
commercial
storage facilities -- prior distribution for processing or sale. Typically,
the grain is
stored in the storage bins during fall and winter.
Temperature changes due to changing seasons result in an unequal
temperature distribution within the grain stored inside the storage bin
causing natural
convection of air through the grain and causing moisture to migrate therewith.
The
moisture then gathers in the top portion of the stored grain causing it to
spoil.
Depending on the temperature and the moisture content of the grain spoilage
occurs
within weeks or even days.
To prevent spoilage of grain stored in storage bins grain aeration
systems or grain drying systems are employed, in grain aeration systems a fan
provides a flow of outside air into and through the stored grain.
Unfortunately,
aeration systems are relatively complex and expensive to manufacture, install,
and
operate. Furthermore, in conditions of high humidity of the outside air the
aeration is
ineffective in preventing spoilage of the grain. Grain drying systems are more
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effective in humid conditions of the outside air, but are even more expensive
to
operate than aeration systems and care must be taken that the stored grain is
not
damaged due to too high temperatures of the heated air provided by the grain
drying
system.
SUMMARY OF THE INVENTION
According to one aspect of the present invention, there is provided a
ventilation system for ventilating particulate materials disposed in a storage
bin
comprising:
an elongated hollow body for being disposed in proximity of a center of
the storage bin and oriented substantially vertical;
the elongated hollow body having a plurality of apertures arranged
such that airflow into the elongated hollow body from the particulate material
in the
storage bin is enabled while transmission of the particulate materials into
the
elongated hollow body is substantially prevented;
a venting arrangement for venting the airflow from inside the elongated
hollow body such that the airflow can be discharged to an exterior of the
storage bin;
and,
a support mechanism adapted for holding the elongated hollow body,
during use of the ventilation system, in a position of the elongated hollow
body such
that a bottom end of the elongated hollow body is spaced from a bottom of the
storage bin;
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the support mechanism comprising a top holding mechanism for
mounting to a top structure of the storage bin and a bottom support mechanism
connected to a bottom portion of the elongated hollow body;
and means for providing a force locating the bottom end of the
elongate hollow body at the bottom support wherein said means is arranged such
that the bottom end of the elongate hollow body is released from the bottom
support
mechanism in response to a transverse load on the elongate hollow body greater
than a predetermined value determined by the force so as to be suspended by
the
top holding mechanism;
and wherein said means operates so that the bottom end is reengaged
with the bottom support mechanism when the bottom end returns to the bottom
support mechanism.
According to a second aspect of the invention there is provided a
ventilation system for ventilating particulate materials disposed in a storage
bin
comprising:
an elongated hollow body for being disposed in proximity of a center of
the storage bin and oriented substantially vertical;
the elongated hollow body having a plurality of apertures arranged
such that airflow into the elongated hollow body from the particulate material
in the
storage bin is enabled while transmission of the particulate materials into
the
elongated hollow body is substantially prevented;
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=
a venting arrangement for venting the airflow from inside the elongated
hollow body such that the airflow can be discharged to an exterior of the
storage bin;
and,
a support mechanism adapted for holding the elongated hollow body,
during use of the ventilation system, in a position of the elongated hollow
body such
that a bottom end of the elongated hollow body is spaced from a bottom of the
storage bin;
the support mechanism comprising a top holding mechanism for
mounting to a top structure of the storage bin and a bottom support mechanism
connected to a bottom portion of the elongated hollow body;
and means for providing a force between the bottom end of the
elongate hollow body and the bottom support mechanism locating the bottom end
of
the elongate hollow body at the bottom support mechanism wherein said means is
arranged such that the bottom end of the elongate hollow body is releasable
from
the bottom support mechanism so as to be suspended by the top holding
mechanism and is reengaged with the bottom support mechanism when the bottom
end returns to the bottom support mechanism;
wherein the bottom support mechanism comprises a transverse beam
structure extending outwardly from sides of the bottom portion of the elongate
hollow
body to a wall of the storage bin.
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According to a further aspect of the invention there is provided a
ventilation system for ventilating particulate materials disposed in a storage
bin
comprising:
an elongated hollow body for being disposed in proximity of a center of
5 the storage bin and oriented substantially vertical;
the elongated hollow body having a plurality of apertures arranged
such that airflow into the elongated hollow body from the particulate material
in the
storage bin is enabled while transmission of the particulate materials into
the
elongated hollow body is substantially prevented;
a venting arrangement for venting the airflow from inside the elongated
hollow body such that the airflow can be discharged to an exterior of the
storage bin;
and,
a support mechanism adapted for holding the elongated hollow body,
during use of the ventilation system, in a position of the elongated hollow
body such
that a bottom end of the elongated hollow body is spaced from a bottom of the
storage bin:
the support mechanism comprising a top holding mechanism for
mounting to a top structure of the storage bin and a bottom support mechanism
connected to a bottom portion of the elongated hollow body;
and magnet means for providing a force between the bottom end of the
elongate hollow body and the bottom support mechanism locating the bottom end
at
the bottom support mechanism wherein said means is arranged such that the
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bottom end of the elongate hollow body is released from the bottom support
mechanism so as to be suspended by the top holding mechanism;
and wherein said magnet means reengages the force between the
bottom end of the elongate hollow body and the bottom support mechanism when
the bottom end returns to the bottom support mechanism.
The arrangement as described in more detail hereinafter provides a
ventilation system for ventilating particulate materials disposed in a storage
bin. The
ventilation system comprises an extendable elongated hollow body for being
disposed in proximity of a center of the storage bin and oriented
substantially
1.0 vertical. The body comprises a plurality of body sections and when
extended has a
length approximately equal to a distance between a bottom portion of the
storage bin
and a top portion of the storage bin. The body has a plurality of apertures
such that
airflow between inside and outside the body is enabled while transmission of
the
particulate materials into the body is substantially prevented. A holding
mechanism
is is mounted to the body and to at least one of the top portion and the
bottom portion
of the storage bin.
The arrangement described hereinafter may provide the advantage
that it provides a ventilation system for ventilating particulate materials
disposed in a
storage bin that is simple and easy to install.
20 A further advantage which may be provided is that it provides a
ventilation system for ventilating particulate materials disposed in a storage
bin that
uses naturally occurring convection.
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BRIEF DESCRIPTION OF THE DRAWINGS
A preferred embodiment of the present invention is described below
with reference to the accompanying drawings, in which:
FIGS. la and lb are simplified block diagrams illustrating in cross
sectional views of a storage bin natural convection occurring within grain
stored
therein without and with a ventilation system according to a preferred
embodiment of
the invention;
FIG. 2a is a simplified block diagram illustrating a cross sectional view
of the ventilation system according to a preferred embodiment of the invention
installed in a storage bin;
FIG. 2b is a simplified block diagram illustrating a side view of a portion
of the body of the ventilation system according to a preferred embodiment of
the
invention;
FIGS. 3a and 3b are simplified block diagrams illustrating a bottom
holding mechanism for mounting the ventilation system according to a preferred
embodiment of the invention to the bottom of the storage bin;
FIGS. 3c and 3d are simplified block diagrams illustrating a top holding
mechanism for mounting the ventilation system according to a preferred
embodiment of the invention to the top of the storage bin;
FIG. 3e is a cross-sectional view of an embodiment of a bottom holding
mechanism having a rare earth magnet therein;
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FIG. 3f is an upper element of a free standing base;
FIG. 3g is a view of the upper element of the free standing base of
FIG. 3f attached to a lower element of the free standing base;
FIG. 3h is a perspective view of a connector for attaching one or more
s extension pipes to the lower end of the body of the ventilation device in
one
embodiment of the present invention;
FIGS. 4a to 4c are simplified block diagrams illustrating a telescopic
extendable body of the ventilation system according to a preferred embodiment
of
the invention;
FIGS. 4d and 4e are simplified block diagrams illustrating an
alternative embodiment of a telescopic extendable body of the ventilation
system
according to embodiments of the invention; and,
FIGS. 5a to 5d are simplified block diagrams illustrating various
connecting mechanisms for connecting a plurality of body sections of the
ventilation
system according to embodiments of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Unless defined otherwise, all technical and scientific terms used herein
have the same meaning as commonly understood by one of ordinary skill in the
art
to which the invention belongs. Although any methods and materials similar or
equivalent to those described herein can be used in the practice or testing of
the
present invention, the preferred methods and materials are now described.
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While the description of the preferred embodiments herein below is
with reference to a ventilation system for ventilating grain disposed in a
storage bin,
it will become evident to those skilled in the art that the embodiments of the
invention are not limited thereto, but are also applicable for ventilating
numerous
other stored particulate materials where a reduction in moisture content
and/or a
substantially equal temperature distribution within the stored particulate
materials is
desirable.
Furthermore, while the description of the preferred embodiments
herein below is with reference to a ventilation system for ventilating grain
disposed in
a storage bin having a circular cross section, it will become evident to those
skilled in
the art that the embodiments of the invention are not limited thereto, but are
also
applicable for storage bins having other cross sections such as, for example,
cross
sections of square or rectangular shape.
Referring to FIGS. 1a and 1 b, a cross sectional view through a filled
state of the art grain storage bin 10 is shown, illustrating natural
convection
occurring therein during fall and winter without a ventilation system and with
a
ventilation system according to embodiments of the invention, respectively.
Grain is
disposed within the storage bin 10 to a fill level 14. Cooler temperatures
during fall
and winter cause an unequal temperature distribution within the stored grain
with
zones of lower temperature 16 located in proximity to the outside walls of the
storage bin 10 and zones of higher temperature 18 located in proximity to the
center
of the storage bin 10. The unequal temperature distribution causes a natural
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convection to occur inside the stored grain as indicated by the arrows.
Without a
ventilation system, as illustrated in FIG. la, the natural convection causes a
substantially closed circuit of airflow within the stored grain and warm moist
air is
transported in proximity to the center of the storage bin 10 to the top of the
stored
s grain. Due to cooler temperatures in the top portion 20 of the stored grain
the
moisture condenses and gathers therein. With the ventilation system 100
according
to embodiments of the invention, as illustrated in FIG. 1b, the closed circuit
of natural
convection is interrupted and the warm moist air is guided to the outside
through the
ventilation system 100 and opening 11 between the top portion of the storage
bin 10
10 and lid 12 as indicated by the arrows. Thus, the moisture is guided to
the outside
and prevented from gathering. Furthermore, guiding the warm air to the outside
equalizes the temperatures between the zones of warmer temperatures and cooler
temperatures in the stored grain.
Referring to FIGS. 2a and 2b, a ventilation system 100 for ventilating
grain disposed in a storage bin according to a preferred embodiment of the
invention
is provided. The ventilation system comprises an extendable elongated hollow
body
102, a holding mechanism 106, 110 mounted to the body 102, and a cap 108. The
ventilation system 100 is disposed in proximity of a center of the storage bin
10 and
oriented substantially vertical. The body 102 comprises a plurality of body
sections,
as will be described herein below, and when extended has a length
approximately
equal to a distance between a bottom portion of the storage bin and a top
portion of
the storage bin 10 such that a top portion of the ventilation system 100 is
disposed
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above the fill level 14 and in proximity to the opening 11. The body 102 has a
plurality of apertures 104 such that airflow between inside and outside the
body 102
is enabled while transmission of the grain into the body 102 is substantially
prevented.
Preferably, the body 102 has a circular cross section, but is not limited
thereto, and various other shapes are also employable such as, for example,
square, rectangular, triangular, or ellipsoidal. The size of the cross section
is
determined, for example, in dependence upon a predetermined airflow to be
enabled
by the ventilation system 100 for ventilating the stored grain.
Preferably, the apertures 104 are of circular shape, as illustrated in
FIG. 2b, but are not limited thereto, and various other shapes are also
employable
such as, for example, square, rectangular, triangular, ellipsoidal, or
combinations
thereof. Size and distribution of the apertures are determined, for example,
in
dependence upon the size of the grain, a predetermined airflow to be enabled
by the
ventilation system 100 for ventilating the stored grain. Further preferably,
the
apertures 104 are equally distributed, as illustrated in FIG. 2b. Optionally,
the
apertures 104 are distributed in an unequal fashion, for example, providing
more
apertures 104 on a middle portion of the body 102 -- which is likely disposed
in
proximity to a warmer zone of the stored grain than a top and bottom portion
of the
body 102 -- and less or no apertures 104 on the top and bottom portion of the
body
102.
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Preferably, the body sections are made using standard technology
such as, for example, forming metal tubing from sheet metal, for example,
galvanized steel or aluminum' having the apertures 104 cut therein using laser
cutting technology or a punch press. Alternatively, other manufacturing
technologies
5. and materials are employed such as, for example, plastic molding
techniques.
Further alternatively, a rigid body structure, for example, made of rods and
rings
outlining the shape of each of the body sections, is surrounded with an
appropriate
wire mesh.
Preferably, the top of the body 102 is covered for preventing disposal
of grain inside the body 102 when filled into the storage bin 10 through
opening 11
by providing a cap 108 mounted to a top portion of the body 102. The cap 108
is
shaped -- for example, forming a pyramid, a cone, or a half sphere -- for
dispersing
the grain into the storage bin 10 when impinging thereupon.
Further preferably, the cap 108 comprises a plurality of apertures 109
such that airflow between inside and outside the body 102 is enabled while
transmission of the particulate materials into the body 102 is substantially
prevented.
The apertures 109 are, for example, of same shape and size as the apertures
104.
Optionally, the apertures 109 are of different shape and/or size depending,
for
example, on the orientation of a cap surface with respect to the impinging
grain.
Further optionally, the apertures 109 are omitted and the airflow is guided to
the
outside, for example, through the apertures 104 disposed in the top portion of
the
body 102, or a predetermined gap between the body 102 and the cap 108.
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Preferably, the holding mechanism comprises a bottom holding
mechanism 106 mounted to a bottom portion of the body 102 for being mounted to
a
bottom structure of the storage bin 10 and a top holding mechanism 110 for
being
mounted to a top structure of the storage bin 10, as illustrated in FIG. 2a.
Referring to FIGS. 3a and 3b, a preferred embodiment of a bottom
holding mechanism 106 is provided. The bottom holding mechanism 106 comprises
a base 106B having a flange or a collar 106A mounted thereupon snugly
accommodating the bottom portion of the body 102 therein, as illustrated in
FIG. 3a.
The base 106B is mounted to a telescopic extendable support 106C which allows
a
vertical adjustment of the body 102 using screw mechanism 106D with the
consequence that the bottom holding mechanism is arranged to extend downwardly
from the bottom end to the bottom structure of the storage bin and is
extendible and
retractable.
Support base 106E of the extendable support 106C is mounted to
extendable beam structure 106F using, for example, U-shaped mounting
mechanisms 106G. The extendable beam structure 106F has end portions 106H
mounted thereto for interfacing with a sloped wall portion of a hopper. Thus
the
bottom holding mechanism comprises a transverse beam structure extending
outwardly from sides of the bottom portion of the elongate hollow body to a
wall of
the storage bin. Preferably, each of the end portions 106H comprises a flat
surface
having a substantially same slope as a sloped wall portion of the hopper,
which is
screwed, welded or otherwise securely fastened to the sloped wall portion.
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Alternatively, the end portions are held in place by friction using, for
example, a rubber layer disposed between the flat surface and the sloped wall
portion. Optionally, the beam structure comprises more than two end portions.
Further alternatively, the bottom portion of the body 102 is mounted to the
base
106B using, for example, angle fittings.
Optionally, the support base 106E is, for example, directly mounted to
the floor structure of the storage bin 10 using screws, bolts, welding or
other secure
fastenment means.
In the embodiment of the bottom holding mechanism of FIG. 3e, a rare
earth magnet 106K is positioned within a cavity 106L in the bottom holding
mechanism, the rare earth magnet 106K being adapted to directly or indirectly
magnetically engage with the walls and/or bottom of the cavity and being
adapted to
directly or indirectly magnetically engage with the lower end of the steel
body 102
[in] with the consequential result that that the bottom holding mechanism at
the
bottom end of the elongated hollow body is arranged such that the bottom end
of the
elongate hollow body is releasable in response to a transverse load on the
elongate
hollow body areater than a predetermined value determined by the force from
the
bottom holding mechanism and reengaged re engagablo therewith by the magnetic
force when it returns to the initial position.
While the bottom holding mechanism of FIGS. 3a and 3b may be
readily used in hopper or "V" bottom type bins, in one embodiment of the
present
invention, in place of the bottom holding mechanism of FIGS. 3a and 3b, a free
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standing base as illustrated in FIGS. 3f and 3g may be used in flat bottom
bins and
the like, the lower element of the free standing base 107D being positioned or
securely fastened to the bottom or floor of the flat bottom bin (by way of,
for
example, bolts passing through holes 107F in the lower element of the free
standing
5 base 107D and into the bottom or floor of the flat bottom bin, or by
other fastenment
means known to a person skilled in the art), the upper element of the free
standing
base (having a tubular element 107A welded or otherwise securely fastened to a
base element 107B, the upper element of the free standing base being for
example
bolted 107E through holes 107C, welded or otherwise securely fastened to the
lower
10 element of the free standing base illustrated in FIG. 3f) extending in a
generally
vertical orientation, and being adapted for engagement with the bottom of the
lower
end of the steel body 102 in a manner known to a person skilled in the art,
and
preferably by positioning the upper element of the free standing base 107A
within,
and in snug engagement with the inside surface of the hollow lower end of the
steel
15 body 102 in a known manner, it being understood that alternative methods
for such
attachment are known to a person skilled in the art.
With reference to FIG. 3h a connector 109 is provided, which may, for
example, be inserted into the lower portion of the body to couple the body to
an
extension pipe (not shown), the connector ends 109A being of reduced diameter
2o relative to the inside diameter of the body and extension pipe (not shown),
the
connector ends 109A being snugly insertable into the interior of the lower
portion of
the body and into the interior of the extension pipe (not shown), the
connector ends
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109A coupling the body to the extension pipe to thereby extend the body as
needed
or desired.
Referring to FIGS. 3c and 3d, a preferred embodiment of a top holding
mechanism 110 is provided. The cap 108 is mounted to the top portion of the
body
102 using at least two angle fittings 120 mounted to top portion of the body
102 via
screws 122 and screw 126. In FIG. 3d only one angle fitting is shown for
simplicity.
Chain 128 is mounted to the angle fitting 120 via angle fitting 124 and screw
126. At
least two chains 128 are then mounted to the top portion of the storage bin
10, for
example, to a ring structure surrounding opening 11. For example, the top
holding
1.0 mechanism 110, as illustrated in FIGS. 3c and 3d, enables hanging of
the ventilation
system 100 from the top portion of the storage bin 10 during installation.
Alternatively, the chains 128 are mounted to a ring structure surrounding the
top
portion of the body 102.
Preferably, the body 102 comprises a plurality of body sections which
is are mounted together during installation inside the storage bin 10 or
telescoping
body sections enabling telescopic extension of the body 102 during
installation
inside the storage bin for providing a body 102 having a length approximately
equal
to a distance between a bottom portion of the storage bin 10 and a top portion
of the
storage bin 10. Providing an extendable body 102 substantially facilitates
installation
20 Of the ventilation system 100 inside the storage bin 10, for example,
when installed
as a retrofit. The length of the body sections is determined such that
handling of the
same is facilitated -- for example, during transport by having a length that
easily fits
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on a truck, as well as during installation by having a length that allows
provision of
the ventilation system 100 into the storage bin through a manhole in the
bottom
portion of the storage bin, thus obviating the use of a crane for lifting the
ventilation
system 100 through the opening 11 in the top of the storage bin 10.
Referring to FIGS. 4a to 4c, a preferred embodiment of a telescopic
extendable body 102 of a ventilation system according to the invention is
shown.
The telescopic extendable body 102 comprises a plurality of telescoping body
sections 102A, 102B, 102C. Each telescoping body section 102A, 102B, 102C has
a
constant cross section along longitudinal axis 103. The cross sections are
varied
such that a successive body section is accommodated inside a previous body
section. Preferably, the size of the cross sections of successive body
sections 102A,
102B, 1020 is decreasing from the bottom body section 102A to the top body
section 102C. Prior installation, the top body section 1020 is accommodated
inside
the body section 102B which itself is accommodated inside the bottom body
section
102A, as illustrated in FIGS. 4a and 4b. During installation the top body
section
1020 is, for example, pulled towards the top of the storage bin 10 for
extending the
body 102, as illustrated in FIG. 4c. End portions of the telescoping body
sections
102A, 102B, 102C are provided with respective stop mechanisms 160, 162 -- for
example, inside and outside stop rings -- mounted to the inside and outside of
the
respective body sections 102A, 102B, 1020 as illustrated in FIG. 4b. When the
body
102 is extended, inside stop ring 162 abuts outside stop ring 160, as
illustrated in
FIG. 4c. As is evident, the preferred embodiment is not limited to three body
sections
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as illustrated in FIGS. 4b and 4c, but various other numbers of body sections -
- two,
four or more -- are also applicable.
Alternatively, as illustrated in FIGS. 4d and 4e, the telescoping body
sections 102A, 102B, 102C are tapered such that when the body 102 is extended
an
end portion outside surface 150 of the second body section 102B interacts with
an
end portion inside surface 152 of the first body section 102A providing, for
example,
a snugly fit.
Further alternatively, separate body sections 102A, 102B, are mated
during installation inside the storage bin 10. Referring to FIGS. 5a to 5d,
various
embodiments of a mechanism for mating a plurality of body sections 102A, 102B
are
shown. As illustrated in FIG. 5a, an end portion of second body section 102B
is
shaped for being mated with a corresponding end portion of a first body
section
102A. The second body section 102B comprises a flange 130 for accommodating
the corresponding end portion 132 of the first body section 102A using, for
example,
a snugly fit. Alternatively, the body sections 102A and 102B comprise
respective
flanges 134 which are mounted together using screws 136, as illustrated in
FIG. 5b.
Further alternatively, connecting element 138 is interposed between the body
sections 102A and 102B, as illustrated in FIG. 5c. The connecting element 138
accommodates respective end portions 140A and 140B of body section 102A and
102B using, for example, a snugly fit. Further alternatively, each body
section 102A,
102B is tapered such that an end portion outside surface 142 of a first body
section
102A interacts with an end portion inside surface 144 of a second body section
102B
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providing, for example, a snugly fit, as illustrated in FIG. 5d. Optionally,
the body 102
is tapered -- for example, having a smaller cross section at the top than at
the
bottom -- and the end portions are shaped for mating corresponding body
sections
of a predetermined sequence of body sections forming the tapered body 102.
The present invention has been described herein with regard to
preferred embodiments. However, it will be obvious to persons skilled in the
art that
a number of variations and modifications can be made without departing from
the
scope of the invention as described herein.
