Grain flow regulator for a grain dryer

Information

  • Patent Grant
  • 6457256
  • Patent Number
    6,457,256
  • Date Filed
    Friday, February 16, 2001
    23 years ago
  • Date Issued
    Tuesday, October 1, 2002
    22 years ago
Abstract
An apparatus for controlling grain flow within a column of a grain dryer is disclosed. The grain dryer includes a metering roll positioned to contact grain advancing out of a discharge opening of the column. The grain dryer further includes a regulator member which is movable between a flow regulating position and a trash escape position. The regulator member contacts either the metering roll, or grain supported by the metering roll when the regulator member is positioned in the flow regulating position. The regulator member is spaced from the metering roll by a distance sufficient to enable a trash object to advance between the regulator member and the metering roll when the regulator is positioned in the trash escape position. A method of controlling grain flow within a column of a grain dryer is also disclosed.
Description




BACKGROUND OF THE INVENTION




The present invention relates generally to a grain dryer, and more particularly to an apparatus and method for metering grain in a grain dryer.




In many instances, agricultural grain products must be stored for an extended period of time prior to being used. However, prior to storage, it is necessary to dry the grain to a condition in which it is less subject to molding or other deterioration. Accordingly, it has become known to remove moisture from grain by passing the grain through a grain dryer prior to storage.




Grain dryers typically have a plenum chamber through which heated air is advanced. The grain is passed through columns which surround the plenum chamber. Each column includes an inner perforated wall that is in fluid communication with the plenum chamber and an outer perforated wall which is in fluid communication with the ambient environment surrounding the grain dryer. As the grain moves through the column, heated air from the plenum chamber passes through the inner perforated wall, through the flow of grain, and out through the outer perforated wall. As the heated air moves through the flow of grain, moisture is removed from the grain.




To control the amount of moisture removed from the grain, it is necessary to precisely control the flow rate of the grain through the grain column. In particular, grain that remains in the grain column and is exposed to the heated air for an extended period of time may become too dry and even catch on fire, whereas grain that passes quickly through the grain column may retain an undesirable amount of moisture. To control the flow rate of grain through the grain column, a metering roll is utilized at a discharge opening of the grain column. In particular, the metering roll is located in a relatively narrow grain flow metering passage, and rotation of the metering roll within the metering passage causes grain to be advanced through the grain column at a desired rate. Controlling the speed of rotation of the metering roll controls the flow rate of grain through the grain dryer which, in turn, controls the amount of moisture removed from the grain.




A problem with grain dryers that have heretofore been designed is that trash objects can accumulate at or near the metering roll within the metering passage. In particular, high volume grain harvesting techniques now used cause a variety of trash objects to become intermixed with the grain as the grain is harvested. Typically, the trash objects include stalks, corn cobs, and other non-grain material. Because the flow of grain through the grain column is controlled by rotation of the metering roll within the metering passage, the trash objects tend to accumulate at or near the metering roll within the metering passage. The trash objects that accumulate at or near the metering roll in the metering passage tend to disturb the proper flow of grain through the grain column thereby resulting in an improper amount of moisture being removed from the grain. In extreme cases, the trash objects may substantially block the flow of grain through the relatively narrow grain flow metering passage. This, in turn, may cause blockage of the flow of grain through the grain column, thereby causing the grain to be susceptible to catching on fire due to the grain being exposed to the heated air from the plenum chamber for an extended period of time.




What is needed therefore is an apparatus and method for accurately metering grain in a grain dryer which overcomes one or more of the above-mentioned disadvantages.




SUMMARY OF THE INVENTION




In accordance with a first embodiment of the present invention, there is provided a grain dryer. The grain dryer includes a grain column through which grain may flow. The grain column includes a discharge opening. The grain dryer further includes a metering roll positioned to contact grain advancing out of the discharge opening of the grain column. The grain dryer yet further includes a regulator member which pivots between a flow regulating position and a trash escape position. The regulator member contacts either the metering roll, or grain supported by the metering roll when the regulator member is positioned in the flow regulating position. The regulator member is spaced from the metering roll by a distance sufficient to enable a trash object to advance between the regulator member and the metering roll when the regulator member is positioned in the trash escape position.




In accordance with a second embodiment of the present invention there is provided an apparatus for controlling grain flow within a column of a grain dryer. The grain dryer includes a metering roll positioned to contact grain advancing out of a discharge opening of the column. The grain dryer further includes a regulator member which is movable between a flow regulating position and a trash escape position. The regulator member contacts either the metering roll, or grain supported by the metering roll when the regulator member is positioned in the flow regulating position. The regulator member is spaced from the metering roll by a distance sufficient to enable a trash object to advance between the regulator member and the metering roll when the regulator is positioned in the trash escape position.




In accordance with a third embodiment of the present invention there is provided a method of controlling grain flow within a column of a grain dryer. The method includes the steps of rotating a metering roll so that grain advancing out of a discharge opening of the column is transported by the metering roll from a first side of the metering roll to a second side of the metering roll. The method further includes the step of positioning a regulator member in contact with either the metering roll, or grain supported by the metering roll during the rotating step whereby grain flow between the metering roll and the regulator member is restricted. The method yet further includes the step of moving the regulator member away from the metering roll by a distance sufficient to enable a trash object to advance between the regulator member and the metering roll after the positioning step.




It is an object of the present invention to provide a new and useful apparatus for controlling grain flow within a column of a grain dryer.




It is another object of the present invention to provide an improved apparatus and method for controlling grain flow within a column of a grain dryer.




It is still another object of the present invention to provide an apparatus for controlling grain flow within a column of a grain dryer which allows a trash object to advance through the grain dryer without significantly affecting the overall grain flow rate within the column of the grain dryer.




It is yet another object of the present invention to provide an apparatus for controlling grain flow within a grain column of a grain dryer which reduces the likelihood that the grain column will become partially or totally blocked by trash objects during operation of the grain dryer.




It is moreover another object of the present invention to provide an apparatus for controlling grain flow within a grain column of a grain dryer which reduces the likelihood that the grain flowing through the grain column will catch on fire during operation of the grain dryer.




It is another object of the present invention to provide an apparatus for controlling grain flow within a grain column of a grain dryer which is relatively inexpensive to manufacture.




It is another object of the present invention to provide an apparatus for controlling grain flow within a grain column of a grain dryer which is relatively durable.




The above and other objects, features, and advantages of the present invention will become apparent from the following description and attached drawings.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a perspective view of a grain dryer which incorporates the features of the present invention therein;





FIG. 2

is partial cut away perspective view of the grain dryer of

FIG. 1

, showing the plenum chamber and a number of grain columns;





FIG. 3

is fragmentary perspective view of the inside of the grain dryer of

FIG. 1

, showing a number of inner perforated walls, a number of regulator members, and a transport auger;





FIG. 4

is a fragmentary cross sectional view of the grain dryer of

FIG. 1

, showing metering rolls and regulator members;





FIG. 5

is a fragmentary cross sectional view of the left side of the grain dryer of

FIG. 2

showing the relative geometry of the discharge opening, metering roll, and grain support member (note that the grain is shown removed from the grain dryer for clarity of description);





FIG. 5A

is a fragmentary side elevational view of the interior of the grain dryer taken along line


5


A—


5


A of

FIG. 5

, as viewed in the direction of the arrows (note that the metering roll and regulator member is shown removed for clarity of description);





FIG. 5B

is a fragmentary cross sectional view of the left side of the grain dryer of

FIG. 2

, but showing a trash object located in a metering passage of the grain dryer;





FIG. 5C

is a view similar to

FIG. 5B

but showing the trash object advancing between the metering roll and the regulator member;





FIG. 5D

is a view similar to

FIG. 5C

, but showing the trash object advanced to a position beyond the metering roll;





FIG. 6

is a fragmentary cross sectional view of the regulator member of

FIG. 5D

;





FIG. 7A

is a fragmentary perspective view of the dump door of the grain dryer of

FIG. 1

, note that the dump door is shown in the closed position;





FIG. 7B

is an enlarged side elevational view of the grain dryer components which are encircled in FIG.


7


A and indicated as

FIG. 7B

;





FIG. 7C

is a fragmentary perspective view of the dump door of

FIG. 7A

, but showing the dump door in the open position;





FIG. 7D

is an enlarged side elevational view of the grain dryer components which are encircled in FIG.


7


C and indicated as

FIG. 7D

;





FIG. 8A

is a view similar to

FIG. 5

, but showing a residual amount of grain on the grain support member after a grain drying operation (note that the grain support member is shown positioned in a grain support position); and





FIG. 8B

is a view similar to

FIG. 8A

, but showing the grain support member positioned in a cleaning position.











DESCRIPTION OF THE PREFERRED EMBODIMENT




While the invention is susceptible to various modifications and alternative forms, a specific embodiment thereof has been shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that there is no intent to limit the invention to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.




Referring now to

FIGS. 1 and 2

, there is shown a grain dryer


10


. The grain dryer


10


includes a grain inlet


12


positioned on an upper portion of the grain dryer


10


. Grain from a grain source


14


is advanced through the grain inlet


12


to an inlet channel


16


defined in the upper portion of the grain dryer


10


. An inlet auger


18


is positioned within the inlet channel


16


as shown in FIG.


2


. An inlet motor


20


is operable to rotate the inlet auger


18


in the general direction of arrow


22


. As the inlet auger


18


is rotated in the general direction of arrow


22


, the rotating helical blade defined in the outer surface of the inlet auger


18


causes the grain in the inlet channel to advance in the general direction of arrow


24


.




The grain dryer


10


further includes a forward wall


25


, a number of columns


26


, and an aft wall


27


which cooperate to define a plenum chamber


28


. An upper portion of each of the columns


26


is in fluid communication with the inlet channel


26


. As the grain is advanced in the inlet channel


16


, grain flows from the inlet channel


16


to fill each of the columns


26


(see FIG.


2


). The lower portion of each of the columns


26


is in fluid communication with a metering assembly


30


which controls the flow of grain out of the lower portion of each of the columns


26


.




Each of the columns


26


includes an inner perforated wall


32


and an outer perforated wall


34


. The inner perforated wall


32


allows fluid communication between the interior chamber


28


and the grain that is contained within the column


26


. In particular, the perforations in the inner perforated wall


32


are large enough to allow air flow through the inner perforated wall


32


, but small enough to prevent grain from passing from the column


26


to the plenum chamber


28


of the grain dryer


10


. The outer perforated wall


34


allows fluid communication between the grain contained in the columns


26


and the ambient environment surrounding the grain dryer


10


. In a similar manner, the perforations in the outer perforated wall


34


are large enough to allow air flow through the outer perforated wall


34


, but small enough to prevent from grain from passing from the column


26


to the exterior of the grain dryer


10


. In addition, each of the grain columns


26


is separated from adjacent grain columns


26


by a divider


29


(see FIG.


3


).




The grain dryer


10


further includes a heating unit


40


which is operable to draw ambient air from the environment, heat the ambient air, and advance the heated air into the plenum chamber


28


. It should be appreciated that the heated air in the plenum chamber


28


passes though the inner perforated wall


32


in the general direction of arrow


42


(shown in FIG.


2


). The heated air then passes through the flow of grain in each of the columns


26


so as to heat and remove moisture from the grain. The heated air then exits the grain dryer


10


through the outer perforated wall


34


in the general direction of arrow


44


(shown in FIG.


2


). It should be appreciated that the amount of moisture removed from the grain is a function of (i) the amount and temperature of the heated air supplied to the plenum chamber


28


by the heating unit


40


, and (ii) the amount of time that the grain is exposed to the flow of the heated air that passes from the plenum chamber


28


, through the inner perforated wall


32


, through the flow of grain, and out to the ambient environment through the outer perforated wall


34


.




Referring to

FIG. 3

, there is shown the lower portion of the grain dryer


10


. The grain dryer


10


further includes a transport bin


80


located in the lower portion of the grain dryer


10


. A transport auger


82


is positioned within the transport bin


80


. A transport motor (not shown) is operable to rotate the transport auger


82


in the general direction of arrow


21


. As the transport auger


80


is rotated in the general direction of arrow


21


, the rotating helical blade defined in the outer surface of the transport auger


82


causes grain in the transport bin


80


to advance in the general direction of arrow


23


. From the transport bin


80


, the grain advances to a grain outlet


84


(shown in FIGS.


1


and


2


), where the grain exits the grain dryer


10


. A cover


83


is positioned above the transport auger


82


to isolate the transport auger


82


from the plenum chamber


28


. Note that a substantial portion of the cover


83


is shown removed in

FIG. 3

for clarity of description.




Referring now to

FIGS. 4 and 5

there is shown the lower portion of the interior of the grain dryer


10


. The inner perforated wall


32


includes an upper column wall


43


which is positioned substantially vertically within the grain dryer


10


. The lower portion of the upper column wall


43


defines an upper discharge surface


45


. A grain support member


48


lies below the discharge surface


45


. The outer perforated surface


34


includes a lower column wall


47


. The upper portion of the grain support member


48


defines a lower discharge surface


49


. The lower discharge surface


49


is the surface of the grain support member


48


which lies closest to the upper discharge surface


45


. A discharge opening


46


(shown in

FIG. 5

) is defined by the opening that lies between the upper discharge surface


45


and the lower discharge surface


49


.




It should be appreciated that the size of the discharge opening


46


is one factor that determines the amount of grain that that advances from the grain column


26


. In the preferred embodiment shown, the size D


1


of the discharge opening


46


is greater than or equal to 5.0 inches. More preferably, the size D


1


of the discharge opening


46


is equal to about 6.6 inches. In most metering devices heretofore designed, the discharge opening is generally less than 3.0 inches. A smaller discharge opening has the advantage of allowing more precise control of the flow of grain to the metering apparatus, but has the significant disadvantage of becoming obstructed as trash objects are advanced to the metering apparatus


30


.




Referring now to

FIG. 5A

, the lower discharge surface


49


and the upper discharge surface


45


define a width W which is the width of the discharge opening


46


. The width W is equal to the size D


1


. The discharge opening


46


is further defined by a left lateral sidewall


86


and a right lateral sidewall


88


. The left lateral sidewall


86


and the right lateral sidewall


88


define a length L of the discharge opening


46


. The width W of the discharge opening


46


is substantially uniform along the length of discharge opening


46


. In addition, the length L is substantially uniform along the width of the discharge opening. Thus, the discharge opening


46


has a substantially rectangular shape.




Referring again to

FIG. 5

, the metering apparatus


30


includes a metering roll


50


positioned above the grain support member


48


at a distance away from the discharge opening


46


. By spacing the metering roll


50


apart from the discharge opening


46


by the distance shown in

FIG. 5

, the weight of the grain located in the column


26


is not directly supported by the metering roll


50


. Thus, the metering roll


50


requires less energy to rotate in comparison to metering rolls which support a substantial amount of weight generated by grain in a grain column.




Referring again to

FIG. 4

, it should be appreciated that a second metering roll


50


′ is positioned on the left side of the grain dryer


10


and is substantially identical to the metering roll


50


. Each of the metering rolls


50


,


50


′, is rotatable relative to the respective grain support member


48


. In particular, the metering roll


50


on the left is rotated in the general direction of arrow


58


at the same rate as the metering roll


50


′ is rotated in the general direction of arrow


59


. Both the metering roll


50


and the metering roll


50


′ are driven by a metering motor


60


(shown in phantom in FIGS.


1


and


2


). Since the metering roll


50


′ operates in a substantially identical manner to the metering roll


50


, only the structure and operation of the metering roll


50


will be described in detail.




The metering roll


50


includes a number of vanes


56


. Each of the vanes


56


extend longitudinally along the length of the metering roll


50


(see FIG.


3


). A pair of adjacent vanes


56


forms a bucket


62


which accepts grain flowing over the grain support member


48


. Since the metering roll


50


rotates in the general direction of arrow


58


, the buckets move through the positions shown in

FIG. 4

as


62


A,


62


B,


62


C,


62


D,


62


E, and


62


F. As the metering roll


56


is rotated in the general direction of arrow


58


, grain from the discharge opening


46


begins to fill the bucket


62


and becomes entrapped between the vanes when the bucket


62


is positioned in the position


62


A. As the bucket


62


continues to rotate in the general direction of arrow


58


, additional grain from the discharge opening


46


advances into and becomes entrapped in the bucket


62


when the bucket is in the position shown as


62


B. This slow filling of the bucket


62


helps to ensure the each of the buckets is completely filled as the metering roll


50


is rotated in the general direction of arrow


58


. Thus, as the metering roll


50


is rotated in the general direction of arrow


58


, grain is advanced from a first side of the metering roll


50


proximate to the discharge opening


46


to a second side of the metering roll


50


proximate to the transport bin


80


.




Referring again to

FIG. 5

, the grain support member


48


includes a first end


51


which is positioned in contact with the lower column wall


47


and a second end


53


positioned under the metering roll


50


. A grain presentation section


48


A is interposed between the lower column wall


47


and the metering roll


50


whereas a grain metering section


48


B is positioned under the metering roll


50


. The grain presentation section


48


A includes a substantially planar surface which allows grain to flow from the grain discharge opening


46


to the metering roll


50


. In particular, as the metering roll


50


is rotated in the general direction of arrow


58


, the grain flows from the discharge opening


46


to the metering roll


50


over the grain support member


48


. Note that the lower discharge surface


49


is defined in the substantially planar surface of the presentation section


48


A of the grain support member


48


.




The presentation section


48


A of the grain support member


48


is oriented and configured so as to enhance the flow of grain from the discharge opening


46


to the metering roll


50


. In particular, the grain presentation section defines a line L


1


which forms an angle θ with a horizontal line H


1


. The angle θ has a magnitude which is preferably between zero and thirty degrees. More preferably, the angle θ has a magnitude which is equal to about eighteen degrees. The angle θ accommodates the natural angle of repose of a grain such a corn. The angle of repose is a natural flow angle that a quantity of grain assumes as it exits a discharge opening of a grain column. Orienting the presentation section


48


A to possess the angle θ relative to the horizontal line H


1


facilitates uniform flow of grain from the discharge opening


46


.




It should be appreciated that a significant advantage of the present invention is that the angle θ accommodates the angle of repose of a quantity of grain and allows the grain to flow uniformly from column


26


. In particular, accommodating the angle of repose of the grain causes the grain near the inner perforated wall


32


and grain near the outer perforated wall


34


to advance at substantially the same rate as the grain in the center of the column


26


. It should be appreciated that grain that moves through the column


26


at the same rate will have a substantially similar amount of moisture removed as it passes through the grain dryer


10


. Thus, accommodating the angle of repose of the grain allows the grain in the column


26


to be dried in a substantially uniform manner.




The metering roll


50


defines a vane diameter VD. In particular, the vane diameter VD is defined as the distance between the tips of two vanes, where the two vanes


56


are spaced 180° apart from each other as shown in FIG.


5


. In the preferred embodiment, the vane diameter is greater than or equal to six inches. More preferably, the vane diameter is equal to about seven inches. An advantage to such a large vane diameter VD, is that trash objects are less likely to obstruct the flow of grain through the metering roll


50


.




Referring now to

FIG. 5B

,


5


C, and


5


D, the metering apparatus


30


further includes a regulator member


52


. The regulator member


52


controls the amount of grain advanced by each bucket


62


of the metering roll


50


, regardless of the rotational speed of the metering roll


50


. The regular member


52


pivots about a rod


64


secured to the dividers


29


which separate adjacent columns


26


from each other. In particular, the regulator member


52


pivots between a flow regulating position, shown in

FIG. 5B

, and a trash escape position shown in FIG.


5


C. The regulator member


52


can also be placed in a storage position, shown by the regulator members


52


′ in FIG.


3


. In the flow regulating position, gravity acts to pivot the regulator member


52


in the general direction of arrow


58


. In the flow regulating position, the regulator member


52


is supported by either a vane


56


or the grain positioned in a bucket


62


shown in the position of bucket


62


D of FIG.


4


.




The regulator member


52


and the vanes


56


cooperate to control the amount of grain advanced by the rotation of the metering roll


50


. The slow filling of the buckets


62


caused by rotating the metering roll from the position


62


A to the position


62


D ensures that each of the buckets


62


fills completely with grain as the metering roll


50


is rotated in the general direction of arrow


58


. The weight of the regulator member


52


acting on the grain prevents grain that extends beyond the tip of the vanes


56


from advancing from the discharge opening


46


to the transport bin


80


as the metering roll


50


is rotated in the general direction of arrow


58


.




A trash object


68


may become intermixed with the grain during either the harvesting or storage of the grain. Such trash objects


68


may include corn cobs, plant stalks, leaves or other agricultural non-grain objects. As the grain is advanced toward the metering roll


50


, the trash object


68


is also advanced from the discharge opening


46


to a first position (shown in FIG.


5


C). In the first position, the force of the vanes


56


acting on the trash object


68


causes the trash object


68


to be urged against the regulator member


52


. If the regulator member


52


were fixed, the trash object


68


could become wedged between the vanes


56


and the regulator member


52


, possibly preventing rotation of the metering roll


50


, and stopping the operation of the grain dryer


10


.




However, the pivotal attachment of the regulator member


52


allows the trash object


68


to pass between the vanes


56


of the metering roll


50


and the regular member


52


. In particular, as the trash object


68


moves from the position shown in

FIG. 5B

to the first position shown in

FIG. 5C

, the trash object


68


causes the regulator member


52


to pivot in the general direction of arrow


70


from the flow regulating position (shown in

FIG. 5B

) to the trash escape position (shown in

FIG. 5C

) thereby allowing the trash object


68


to pass between the vanes


56


of the metering roll


50


and the regulator member


52


. From the first position, the trash object


68


passes to a second position in the transport bin


80


(shown in

FIG. 5D

) and thereafter is advanced by the transport auger


82


out of the grain outlet


84


.




It should be appreciated that the regulator member


52


is advantageously weighted so that the regulator member


52


remains in the regulating position when grain is present between the vanes


56


of the metering roll


50


and the regulator member


52


, and moves to the trash escape position when a trash object


68


is placed between the vanes


56


and the regulator member


52


. To this end, an ancillary weight


74


(see

FIG. 6

) is attached to an end of the regulator member


52


by a fastener


75


. The effect of the ancillary weight


74


helps cause the regulator member


52


to be maintained in the regulator position until a trash object


68


of sufficient size is able to urge the regulator member


52


from the flow regulating position to the trash escape position.




Referring now to

FIGS. 7A

,


7


B,


7


C, and


7


D, there is shown an emergency release mechanism


90


positioned on the lower column wall


47


. The emergency release mechanism


90


includes an emergency door


92


which is pivotally secured to a bracket


91


on the lower column wall


47


by a pair of fasteners


94


. The emergency door


92


can rotate about an axis


96


in the general direction of arrows


99


and


100


. The emergency door


92


covers an exit opening


93


defined in the outer perforated wall


34


(see FIGS.


5


A and


7


C). A beveled portion


98


is defined along an upper edge of the emergency release door


92


.




An actuator


102


is also pivotally secured to the bracket


91


by a pair of fasteners


104


such that the actuator


102


can rotate about an axis


106


. The ends of the actuator


102


proximate to the fasteners


104


each include a retaining portion


108


and a notched portion


110


. When the actuator is in a first position (shown in FIGS.


7


A and


7


B), the retaining portion


108


of the actuator


102


holds the beveled portion


98


of the emergency door


92


against the lower column wall


47


. Holding the beveled portion


98


against the lower column wall


47


places the emergency door


92


in a closed position which prevents grain from exiting the grain column


26


via the exit opening


93


(see FIG.


5


B).




When the actuator


102


is rotated in the general direction of arrow


99


, the retaining portion


108


of the actuator


102


is rotated out of contact with the beveled section


98


of the emergency door


92


. The notched portion


110


of the actuator


102


is moved proximate to the beveled portion


98


of the emergency door


92


. The notched portion


110


allows the beveled portion


108


of the emergency door


102


to move away from the lower column wall


47


thereby allowing the emergency door


92


to rotate about the axis


96


in the general direction of arrow


99


into the open position (shown in FIG.


7


C). When the emergency door


92


is placed in the open position, grain from the grain column


26


is allowed to exit the grain dryer


10


through the exit opening


93


(shown in phantom in FIG.


5


B).




It should be appreciated that the emergency door


92


can be used to rapidly empty grain from the grain columns


26


in case of an emergency in the grain dryer


10


. Typically, such emergencies arise when the grain or other material, such as a trash object, catches on fire within the grain dryer.




Referring now to

FIGS. 8A and 8B

, there is shown the interior of the grain dryer


10


after a grain drying operation. It should be noted that an amount of residual grain


112


remains on the grain support member


48


. Because of the shallow angle of the grain support member


48


from the horizontal, the residual grain


112


cannot be advanced by the metering roll


50


. If the residual grain were to remain on the grain support member


48


for an extended period of time (e.g. over a winter season), the residual grain


112


could either rot or sprout, both of which are undesirable.




To remove the residual grain


112


from the grain support member


48


, the grain support member


48


is pivotally secured to the dividers


29


by a rod


116


. In particular, the grain support member


48


pivots from a grain support position (shown in

FIG. 8A

) to a cleaning position (shown in

FIG. 8B

) in the general direction of arrow


118


. When the grain support member


48


is in the grain support position, grain must pass over the metering roll


50


prior to entering the transport bin


80


. When the grain support member


48


is in the cleaning position, grain bypasses under the metering roll


50


and flows directly to the transport bin


80


from the grain support member


48


.




When the grain dryer


10


is full of grain (as shown in

FIGS. 5B

,


5


C, and


5


D), the weight of the grain from the grain column


26


applies a downward force on the grain support member


48


in the general direction of arrow


119


thereby preventing the grain support member


48


from rotating about the rod


116


in the general direction of arrow


118


. Thus, the weight of the grain in the grain column


26


biases the grain support member


48


into the grain support position.




To move the grain support member


48


from the grain support position to the cleaning position, a handle


120


is secured to the grain support member


48


. To access the handle


120


, an access opening


122


is defined in the outer surface of the grain dryer


10


(see

FIG. 7A

) which allows the operator to reach the handle


120


from the exterior of the grain dryer


10


. To move the grain support member


48


from the grain support position to the cleaning position, an operator reaches through the access opening


122


and urges the handle


120


in the general direction of arrow


124


.




Referring again to

FIG. 2

, the grain dryer


10


further includes a grain column temperature sensor


126


, a plenum chamber temperature sensor


128


, and a control unit


130


. The grain column temperature sensor


126


runs through a number of grain columns


26


and is operable to sense the temperature of the grain in the columns


26


and generate a grain column temperature signal in response thereto. The plenum chamber temperature sensor


128


is positioned within the plenum chamber


28


and is operable to sense temperature of the air in the plenum chamber


28


and generate a plenum chamber temperature signal in response thereto. The control unit


130


is operable to receive the grain column temperature signal and the plenum chamber temperature signal and make adjustments to the grain drying operation.




If the grain column temperature signal indicates that the temperature of the grain in the columns


26


is too high, then the control unit


130


can either (i) increase the rate at which the metering roll


50


rotates by increasing the speed of the metering motor


60


thereby decreasing the amount of time that the grain is exposed to the heated air from the plenum chamber


28


, or (ii) decrease the amount of heated air that the heating unit


40


introduces into the plenum chamber


28


. On the other hand, if the grain column temperature signal indicates that the temperature of the grain in the columns


26


is too low, then the control unit


130


can either (i) decrease the rate at which the metering roll


50


rotates by decreasing the speed of the metering motor


60


thereby increasing the amount of time that the grain is exposed to the heated air from the plenum chamber


28


, or (ii) increase the amount of heated air that the heating unit


40


introduces into the plenum chamber


28


.




Operational Summary




During a grain drying operation, grain with a high moisture content is advanced to the inlet


12


of the grain dryer


10


(see e.g. FIG.


2


). The grain advances from the inlet


12


to the inlet channel


16


. From the inlet channel


16


, grain is distributed among a number columns


26


.




A heating unit


40


advances heated air into a plenum chamber


28


. From the plenum chamber


28


, the heated air passes through the inner perforated wall


32


in the general direction of arrow


42


of

FIG. 2

, through the flow of grain in the column


26


and out of the grain dryer through the outer perforated wall


34


in the general direction of arrow


44


of FIG.


2


. As the heated air passes through the flow of grain, moisture is removed from the grain thereby drying the grain. It should be appreciated that the amount of moisture removed from the grain is a function of how long the grain remains within the column


26


.




A metering assembly


30


controls the amount of grain that exits through discharge openings


46


defined in the bottom of the grain columns


26


. The control unit


130


receives plenum chamber temperature signal from the plenum chamber temperature sensor


128


and grain moisture content signals from the moisture sensor


126


and generates a metering roll control signal which controls the rotational speed of the metering roll


50


, and thus the flow rate of grain through the columns


26


.




The relatively large width D


1


of the discharge opening


46


allows a smooth flow of grain from the column


26


to the metering roll


50


. In addition, the magnitude of the width D


1


is large enough to allow trash objects, such as corn cobs and stalks, to pass from the column


26


to the metering roll


50


. Furthermore, the relatively large vane diameter VD of the metering roll


50


helps assure that trash objects will not become lodged in the metering roll


50


as the grain is advanced to the transport bin


80


.




As the grain flows from the discharge opening


46


to the metering roll


50


, the grain passes through a metering passage and over the presentation section


48


A of the grain support member


48


. The presentation section


48


A forms an angle θ with a horizontal line. The magnitude of the angle θ accommodates the angle of repose of a quantity of grain (e.g. corn) exiting the discharge opening


46


of the grain column


26


, and allows the grain to flow uniformly from column


26


. This uniform flow of grain facilitates uniform drying of grain within grain dryer


10


.




In addition to the sizing of the metering roll


50


and the discharge opening


46


, the regulator member


52


also helps to prevent trash objects from becoming jammed in the metering passage, near the metering roll


50


. As the trash object


68


comes into contact with the metering roll


50


, the trash object


68


is advanced in the general direction of arrow


58


by the metering roll


50


(shown in FIG.


5


B). As the trash object


68


advances in the general direction of arrow


58


, the trash object urges the regulator member


52


to move from the flow regulating position (shown in

FIG. 5B

) to the trash escape position (shown in FIG.


5


C). When the regulator member


52


is in the trash escape position, the trash object


68


advances around the vanes


56


of the metering roll


50


to the transport bin


80


(see FIG.


5


D). From the transport bin


80


, grain as well the trash object


68


is advanced to the grain outlet


84


via the transport auger


82


.




Because of the large amount of heat produced by the heating unit


40


, grain or trash objects in the grain column


26


may begin to burn during a grain drying operation. When a fire is detected in the grain dryer


10


, the grain in the column


26


must be rapidly emptied to prevent damage to the grain dryer


10


. To empty the grain from the column


26


, the actuator


102


is rotated in the general direction of arrow


99


about the axis


106


(see FIG.


7


A). Rotation of the actuator


102


in the general direction of arrow


99


moves the retaining portion


108


of the actuator


102


of contact with the beveled section


98


of the emergency door


92


thereby allowing the emergency door


92


to rotate about the axis


96


in the general direction of arrow


99


. As a result, grain exits the column


26


via the exit opening


93


.




After the grain drying operation, grain must be emptied out of the grain dryer


10


. Any grain remaining in the grain dryer


10


over an extended period of time may rot or sprout which is undesirable. Because the grain presentation section


48


A has an angle of between zero and thirty degrees from the horizontal a small amount of residual grain


112


will remain on the grain support member


48


after a grain drying operation. To remove the residual grain


112


from the support member, an operator pushes the handle


120


in the general direction of arrow


124


(see

FIG. 7A

) which moves the grain support member


48


from the grain support position (shown in

FIG. 8A

) to the cleaning position (shown in FIG.


8


B). In the cleaning position, the residual grain


112


flows under the metering roll


50


from the grain support member


48


to the transport bin


80


. From the transport bin


80


, the residual grain


112


is advanced to the grain outlet


84


by the transport auger


82


.




While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description is to be considered as exemplary and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected.




For example, while the emergency release mechanism


90


has been described in detail above and its design possesses many advantages, other designs of emergency release mechanisms may be used in the grain dryer


10


. For instance, another design of an emergency release mechanism which may be substituted for emergency release mechanism


90


includes a slide member which is positionable to cover exit opening


93


during normal operation of the grain dryer


10


. Thereafter, when it is desirable to rapidly empty grain from the grain columns


26


, the slide member can be slid upwardly away from the exit opening


93


so as to allow the escape of grain through the exit opening


93


. The slide member could include an upper flange portion which could be grasped by an operator of the grain dryer


10


. The slide member could be slidingly attached to an outer wall of the grain dryer


10


by a number of retainer guide members which would allow the slide member to be slidable between a closed positioned in which the slide member is positioned over the exit opening


93


and an open position in which the slide member is positioned away from the exit opening


93


so as to allow grain to advance through the exit opening


93


.




In addition, the grain support member


48


is described as having a handle


120


attached thereto as shown in

FIGS. 8A and 8B

which an operator would grasp by reaching through an opening defined in an outer wall of the grain dryer


10


. While such an arrangement has numerous advantages, the grain support member may alternatively have a push rod coupled thereto in place of the handle


120


. The push rod would be accessible to an operator by extending through a small hole defined in the outer wall of the grain dryer


10


. When it is desirable for an operator to remove residual grain


112


from the grain support member


48


, the operator would push an outer end of the push rod toward the outer wall of the grain dryer


10


thereby causing the grain support member


48


to pivot about the rod


116


so as to move the grain support member


48


from the grain support position (shown in

FIG. 8A

) to the cleaning position (shown in

FIG. 8B

) in the general direction of arrow


118


.




Moreover, the flow regulator


52


is depicted in the figures (e.g.

FIGS. 4 and 5

) as having an ancillary weigh


74


attached thereto, and has many advantages thereby. However, it should be appreciated that the ancillary weight


74


may be eliminated if the flow regulator is made from a relatively thick piece of metal to provide increased weight to the flow regulator. This increased weight of the flow regulator


52


would help cause the regulator member


52


to be maintained in the regulator position until a trash object


68


of sufficient size is able to urge the regulator member


52


from the flow regulating position to the trash escape position.




In addition, while the flow regulator


52


is oriented so as to define a plane which intersects a horizontal line to create an angle of about 30° and has many advantages thereby, the flow regulator may be oriented in other manners. For example, the flow regulator


52


may be oriented so as to define a plane which intersects a horizontal line to create an angle of about 45°.



Claims
  • 1. A grain dryer, comprising:a grain column through which grain may flow, said grain column having a discharge opening; a metering roll positioned to receive grain advancing out of said discharge opening; and a regulator member pivotally mounted with respect to said grain dryer for movement between a first position in which said regulator member is in engagement with either (i) said metering roll or with (ii) grain transported by said metering roll and a trash clearance position in which trash transported with said grain conveyed by said metering roll causes said regulator member to move from its first position to its said trash clearance position and wherein said regulator member returns to its said first position once said trash has moved clear of said regulator member.
Parent Case Info

CROSS REFERENCE This application is a continuation of application Ser. No. 09/620,296, filed on Jul. 20, 2000 now U.S. Pat. No. 6,189,235, which in turn is a continuation of application Ser. No. 09/197,974, filed on Nov. 23, 1998, now U.S. Pat. No. 6,101,742. Cross reference is made to copending U.S. patent applications Ser. No. 09/198,995, entitled “Grain Metering System which includes a Pivotable Grain Support Member Positioned between a Metering Roll and a Discharge Opening of a Grain Column” by L. Michael Watson and Phillip C. Middaugh, and Ser. No. 09/197,988, entitled “Grain Metering System for a Grain Dryer having Improved Grain Flow Angle Configuration at Grain Column Discharge Opening” by L. Michael Watson and Phillip C. Middaugh, and Ser. No. 09/198,301, entitled “Grain Metering System for a Grain Dryer having Improved Grain Column Discharge Opening and Metering Roll Configuration” by L. Michael Watson and Phillip C. Middaugh, all of which are assigned to the same assignee as the present invention, and all of were file on Nov. 23, 1998.

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Number Name Date Kind
2552093 Gollbach et al. May 1951 A
2740204 Seltzer et al. Apr 1956 A
3000110 Forth et al. Sep 1961 A
3090133 Kline et al. May 1963 A
3092472 Figley Jun 1963 A
3097934 Applegate Jul 1963 A
3129073 Matthews Apr 1964 A
3233337 Tomlinson Feb 1966 A
3710449 Rathbun Jan 1973 A
3804303 Fasauer Apr 1974 A
4067120 Bradford Jan 1978 A
4152841 Westelaken May 1979 A
4268971 Noyes et al. May 1981 A
4308669 Noyes et al. Jan 1982 A
4463503 Applegate Aug 1984 A
4528848 Häfner Jul 1985 A
5538747 Mueller Jul 1996 A
5651193 Rhodes et al. Jul 1997 A
6035544 Morrison et al. Mar 2000 A
Continuations (2)
Number Date Country
Parent 09/620296 Jul 2000 US
Child 09/785712 US
Parent 09/197974 Nov 1998 US
Child 09/620296 US