BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention generally relates to a drying apparatus
for drying grain like rice, wheat, and barley and malt (hereinafter, grain family),
and more particularly to the drying apparatus which provides uniform density of
a layer for drying grain and malt which should be dried and which are uniformly
spread and stacked to a predetermined depth on a bottom surface of the drying apparatus.
2. Description of the Related Art
As a conventional drying apparatus for drying grain like
rice, wheat, and barley and malt, as shown in figures 1 and 2, as an example, a
bottom surface (halftone plate) 2 through which it is possible for air to flow in
a cylindrical drying chamber 1 in the apparatus, and diffusion means 4 for forming
a layer of grain 3 with a predetermined depth on the bottom surface 2 are provided.
The diffusion means 4 has a rotatable shaft 5 at the center of the cylindrical drying
chamber 1 as shown in figure 1, and a screw conveyer 6 which rotates in the cylindrical
drying chamber is provided with one end at the center of the rotatable shaft 5.
A grain inlet 9 is provided on the upper surface of the cylindrical drying chamber
1. The grain 3 which should be dried is supplied from this inlet 9 to the bottom
surface 2 around the central region of the cylindrical drying chamber 1, then the
grain 3 is moved on the bottom surface 2 sequentially from the central region of
the cylindrical drying chamber 1 to inner walls of the cylindrical drying chamber
1 and a layer having a predetermined depth is formed by spreading the grain all
over the bottom surface 2. Next, heated wind (air flow) is supplied into the cylindrical
drying chamber 1 from a heated wind blower 8 provided on an outer wall 7 of the
cylindrical drying chamber 1. The heated wind passes the grain layer 3 and the bottom
surface 2 then the heated wind exits by flowing under the bottom surface 2. The
grain 3 can be dried by the flow of this heated wind.
The screw conveyer 6 is also provided for up-down and rotatable
movement via two support shafts 11, 12 and elevator devices 13, 14 supporting the
support shafts 11 and 12, respectively. The rotatable shaft 5 is provided in a rotation
driving device 15 mounted at the center of a circular ceiling 13 of the cylindrical
drying chamber 1. Also, the rotatable shaft 5 hangs pivotally downward from the
ceiling 13 and the central support shaft 12 is fixed at a lowest end of the rotatable
shaft 5. An arm 16 which runs in a radial direction is provided on the elevator
device 14 at the lower end of the rotatable shaft 5, a tip of the arm 16 is connected
to the elevator device 13 provided on the upper end of the support shaft 11, and
the elevator device 13 is connected to a movable shaft 18 supported, in which the
upper end of the elevator device 13 is coupled with a supported movable shaft 18
on the ceiling 13 by wheels 17, 17. Also, the lower ends of support shafts 11 and
12 are fixed to the screw conveyer 6. In support shafts 11, 12, those upper parts
are accommodated in the movable shaft 18 and the rotatable shaft 5 with elevator
devices 13 and 14, respectively, and the screw conveyer 6 is moved in the up-and-down
directions by the up-and-down motion of these support shafts 11 and 12.
Also, the arm 16 provided on the rotatable shaft 5 is rotated
by the rotation of the rotatable shaft 5; thereby, the screw conveyer 6 is rotated
around the support shaft 12 side via the support shaft 11 connected though the elevator
device 13 with the tip of the support shaft 11. The inner wall of the drying chamber
of the screw conveyer 6 is moved on a circular rail 19 which is installed on the
bottom floor around the rotatable shaft 5.
Also, a device which drives the screw 20 which drives the
screw conveyer 6 rotationally is provided on the end of the screw conveyer 6, and
the grain which is accumulated on the bottom surface 2 is moved into the periphery
from the central region of the drying chamber by rotating the screw conveyer 6.
SUMMARY OF THE INVENTION
On the other hand, the grain which is spent (discharged)
in the central region from the screw conveyer 6 becomes a uniform depth on the floor,
thereby it appears that the grain layer formed on the drying chamber floor is a
layer where density of the grain is uniform in the appearance inside the layer.
However, it is recognized that density is high in the vicinity of an approximately
central rotatable shaft 12 of the drying chamber 1 which is a place where the grain
is supplied, and the lowest density is in the periphery spaced apart from the central
region, as a result of investigation of an inventor of the present invention. Therefore,
meaningful variation occurs in the passage of the heated wind supplied for drying.
As a result, the degree of drying of the grain is different depending on places
of the drying chamber, and the drying is unbalanced.
The present invention may provide a drying apparatus for
the grain having the diffusion means which makes the grain spent on the drying chamber
floor in the shape of layer. Especially, the drying apparatus for the grain and
a drying method in which variation of density of the grain considered to be in the
shape of the layer is eliminated, and thereby, the grain can be dried uniformly.
Accordingly, there is provided according to one aspect
of the present invention a drying apparatus for the grain family comprising:
- a drying chamber having a floor where the circulation of air is possible,
- wind feed means to supply dry wind in the drying chamber,
- feed means to supply the grain family which should be dried in a predetermined
position on the floor,
- diffusion means to spread the grain family supplied by the drying chamber in
a layer so that the grain is uniform in depth on the floor, and
- plow means which moves with transfer by the diffusion means and plows the layer
of the grain family formed by the diffusion means.
There is also provided according to another aspect of the
present invention a drying method of the grain family, where grain that should be
dried is layered to a predetermined depth on a floor of a drying chamber, and the
grain or malt is dried by supplying a dry wind and circulating the dry wind in the
layer, wherein density of the layer of grain is equalized by spreading the grain
on the floor in a layer and also plowing the layer of the grain.
According to an embodiment of the present invention, the
grain family spent on the drying chamber floor of the drying apparatus is in the
shape of a layer with a uniform depth formed by the diffusion means, and the variation
of density can be eliminated by plowing with the plowing means in the layer of the
grain. By doing so, the grain can be dried uniformly.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects, features and advantages of the present invention
will become more apparent from the following detailed description when read in conjunction
with the accompanying drawings, in which:
DESCRIPTION OF THE PREFERRED EMBODIMENTS
- Fig. 1 is a figure showing a conventional drying apparatus;
- Fig. 2 is a cross-sectional view of A-A section of figure 1;
- Fig. 3 is a figure showing an example of the drying apparatus of the present
- Fig. 4 is a cross-sectional view of B-B section of figure 3;
- Fig. 5 is a figure showing a plow member in detail; and
- Fig. 6 are graphs showing results of examples, in which (a) is a graph in the
case of using the conventional apparatus and (b) is a graph in the case of using
the apparatus of the present invention.
A description will now be given, with reference to the
embodiments according to the present invention.
Figures 3-5 show one example of the drying apparatus of
grain family 10 of the present invention. Basically, the drying apparatus 10 is
a structure such that the plow member of the present invention is provided on the
apparatus shown in figures 1 and 2. Thus, the same reference numbers are used for
the same members as those in figures 1 and 2, and the same explanation is used for
The drying apparatus 10 has the plow member (rake) 30 for
plowing a layer of grain family accumulated in front of the screw conveyer 6 comprising
the diffusion means 4 provided for rotating around the rotatable shaft 5.
The plow member 30 is provided on the central region in
a radial direction along the screw conveyer 6, and is fixed behind and away from
the rotational direction of the screw conveyer 6. As shown in figure 5, the plow
member 30 comprises comb teeth 30a fixed in the metallic angle frame 31 with a comb
shape, and the plow member 30 is hung from a support arm 32 fixed in between support
shafts 11, 12 with wires 34, and it is thus supported.
As shown in figure 5, the wires 34 supports the plow member
30 through two pulley 33a and 33b fixed to support bars 33, 33 fixed to the support
arm 32. A crosspiece member 35 in the crosswise direction is installed below the
support arm 32 between support shafts 11 and 12, and guide tubes 35a, 35a are fixed
to the crosspiece member 35. The wires 34 support the plow member 30 through stoppers
36 attached by the bottom ends of the wires 34. The stoppers 36 each comprises a
head 36a and a shaft 36b, and the shaft 36b is inserted into an introducing tube
35a. As shown in figure 5 the head 36a of the stopper 36 is abutted with the upper
end of the guide tube 35a, and movement to a lower part of the plow member 30 is
On the other hand, a weight 38 is attached between pulleys
33a and 33b of the upper end of the wire 34, so that the depth of the plow member
30 in penetrating the layer of grain family can be adjusted by adjusting with weight
of the plow member 30 for a stroke w shown in figure 5.
In the below description, grain family is dried by using
the drying apparatus 10 of the present invention.
First of all, the grain that should be dried is spent from
the inlet 9 in the ceiling 13 of the drying chamber 1 on the floor 2 of the drying
chamber 1. In this situation, the grain 3 is in a condition that it is accumulated
in the central part of the floor 2 because the inlet 9 is in the vicinity of the
center of the drying chamber 1.
Next, the rotation driving device 15 is started to drive,
the rotatable shaft is rotated, and the device which drives the screw 20 is started,
so that the screw conveyer 6 is driven. The screw conveyer 6 moves the grain in
the central part into wall sides of the drying chamber by rotating the screw. Thus,
the grain 3 which is spent from the inlet and accumulated in the vicinity of the
center of the floor is scattered over the whole floor by rotating the rotatable
shaft 5 of the screw conveyer 6 and the rotation of the screw of the screw conveyer
6 so that the grain is scattered and formed into a uniform layer.
As described above, the drying apparatus 10 of the present
example has the plow member 30 which disturbs the grain accumulated in the shape
of the layer at the central region as well as the diffusion means of the rotatable
screw conveyer 6, so that the inside of the layer of the grain which has accumulated
in the central region is disturbed and mixed well by the plow member, and the density
of the central region where the density tends to rise is lowered and the whole grain
layer has a uniform density distribution.
The drying of the grain is performed by blowing the heated
wind into the drying chamber from the heat wind blower 8. Since the grain has uniform
density over the whole floor, that is, there is no variation of density, the heated
wind goes through uniformly in the layer of the grain and the grain is dried uniformly.
The plow member 30 penetrates by its weight in the layer
of grain and the plow member rotates around the rotatable shaft 5. However, the
depth of the penetration of the plow member 30 is different depending on the kind
of grain to be handled. Therefore, the most suitable depth can be obtained depending
on the kind of grain by adjusting the weight of the weight 38.
Below, an example in which barley ("Ryouhu" produced in
Hokkaido in 2003) was dried by using the drying apparatus of the present example
is described. The barley which contains 48% water before introduction to the drying
apparatus (Green malt; weight 131 t) was used and the drying process was performed
for 17 hours. The targeted degree of dryness was (average water content in malt
after finishing drying) 20%.
From the introduction of the green malt into the drying
apparatus, the diffusion means of the drying apparatus was operated, and the drying
chamber was dried widely. At the same time, the plow means was operated, and disturbed
the grain layer at constant depth (about 10 cm), so that the grain layer was equalized.
After finishing equaling the green malt which was to be
dried, the heated wind was blown immediately and the drying process was performed.
After finishing drying, about 250 g of grain were gathered
every 50 cm where the grain was about 35 cm deep toward the circumference from the
floor center of the drying chamber, and the water contents for these samples were
measured. The measurement of the water content was performed according to "Moisture
content of malt, Section 4 Malt, method 4.2, Analytica-EBC (1998)".
In order to confirm the effect of the embodiment of the
present invention, the same examples were dried using the conventional drying apparatus
which does not have the plow means of the present invention, and its result was
compared to the result of the example of the present invention.
Figure 6 contains graphs showing results of examples, in
which (a) is a graph for using the conventional apparatus without having the plow
means; that is before-improvement and (b) is a graph for using the drying apparatus
of the present invention.
As shown in figure 6(a) before-improvement, there is a
region of high water content around 2-4 m from the center. This is caused by the
region where existing sedimentation density is high in the vicinity of the center
where grain is spent, and it is shown that drying advances toward the wall side.
On the other hand, the whole of the grain layer is a uniform
dry state, as shown in figure 6(b) of the example of the present invention.
From the above example of the present invention, uniform
drying of grain spent in the drying chamber is possible by drying of grain family
using the drying apparatus of the present invention; that is, the drying apparatus
using the diffusion means provided with the plow means.
The plow means 30 of the drying apparatus 10 of the above
example has a length to plow grain in the central region. However, the length of
the plow means 30 is not limited to the above example and the length may be extended
over the whole radius from the center of the floor.
The present invention is not limited to the specifically
disclosed embodiment, and variations and modifications may be made without departing
from the scope of the present invention.
The present application is based on
Japanese priority application No. 2004-170059 filed on June 8, 2004
, the entire contents of which are hereby incorporated by references.