Discharge apparatus adapted to distribute material

Information

  • Patent Grant
  • 6666627
  • Patent Number
    6,666,627
  • Date Filed
    Thursday, May 25, 2000
    24 years ago
  • Date Issued
    Tuesday, December 23, 2003
    21 years ago
Abstract
A discharge apparatus for connection to and covering an airlock material outlet. The discharge apparatus includes an air inlet for at least substantially directing an airstream through an airlock material outlet and toward an interior area defined by an airlock. The discharge apparatus further includes a material directing trough for receiving an airstream and bulk material entrained therein from the airlock. The discharge apparatus also includes an extension member adapted to at least partially define a path of an airstream.
Description




TECHNICAL FIELD




This invention relates generally to apparatus for material distribution, and more particularly to a discharge apparatus for use in an airlock discharge assembly. The invention further relates to an airlock discharge assembly including an improved discharge apparatus.




BACKGROUND OF THE INVENTION




Conventional airlock discharge assemblies are currently used for discharging bulk material from a bulk material discharge assembly. The airlock discharge assemblies frequently entrain the bulk material in a fluid such as air for distribution.





FIG. 1

illustrates one conventional airlock discharge assembly


100


including an airlock


102


and a discharge apparatus


120


. The airlock


102


includes a rotor


103


for rotation inside a housing


105


. The rotor


103


comprises an axle


104


having an axis


107


, a hub


106


mounted on the axle


104


, and vane blades


108


attached at a proximal end to the hub


106


. Typically, the airlock


102


is provided with a plurality of vane blades


108


. Bulk material conveying areas are typically defined between at least a pair of adjacent vane blades


108


, an exterior surface of the hub


106


disposed between the proximal ends of the vane blades


108


, an interior surface of the housing


105


extending between the distal ends of the vane blades


108


, and side portions of the housing


105


adjacent the lateral edges of the vane blades


108


.




In use, bulk material enters an airlock material inlet


112


and fills exposed bulk material conveying area(s). The rotor


103


continues to rotate about the axis


107


until the lateral sides of the bulk material conveying area(s) are registered with the an air inlet


124


and an air outlet


128


defined by the discharge apparatus


120


. An airstream


130


passes through an inlet conduit


122


and an air inlet


124


defined by the inlet conduit


122


in fluid communication with an aperture formed in a side of the housing


105


. The airstream


130


is directed by the air inlet


124


in a direction substantially parallel to the axis


107


and directly into one or more bulk material conveying area(s) from a lateral side of the bulk material conveying area(s). The bulk material is then entrained with the airstream


130


and thereafter discharged through an air outlet


128


defined by an outlet conduit


126


in fluid communication with an aperture formed in the opposite side of the housing


105


. The bulk material is discharged with the airstream


130


through the outlet conduit


126


until it is distributed to the surrounding environment.




The airlock discharge assembly


100


has the benefit of providing a high level of cross-sectional area control, allowing the use of high velocities with a minimal amount of air flow. However, the end portions of the bulk material conveying areas must be kept open since the airstream


130


is required to laterally pass through the bulk material conveying areas. This arrangement typically causes sealing problems between the discharge apparatus


120


and the airlock


102


. In addition, the vane blades


108


of the rotor


103


are exposed to high stresses when shearing objects lodged in the air inlet


124


more frequently in the air outlet


128


, and at the edge of the material inlet


112


. The airlock discharge assembly


100


also experiences excessive wear at the air outlet


128


as entrained bulk material traveling at a high velocity interferes with the housing


105


and other portions of the airlock discharge assembly


100


.





FIG. 2

illustrates another conventional airlock discharge assembly


200


wherein an air inlet


224


directs an inlet airstream


230


below a conventional airlock


202


, rather than directly through a side of the housing


205


and a lateral side of the bulk material conveying areas as with the airlock discharge assembly


100


. The airlock


202


comprises rotor


203


including an axle


204


having an axis


207


, a hub


206


mounted on the axle


204


, and a plurality of vane blades


208


radially extending from an exterior surface of the hub


206


. Bulk receiving areas may be defined between two adjacent vane blades


208


, a portion of the outer surface of the hub


206


disposed between proximal ends of the vane blades


208


, side portions of the housing


205


adjacent the lateral edges of the vane blades


208


, and a portion of the interior surface of the housing


205


extending between the distal ends of the vane blades


208


.




In use, bulk material enters through an airlock material inlet


212


and is received by exposed bulk material conveying area(s). As shown in

FIG. 2

, an airlock material outlet


210


is positioned below a bottom edge position


209


of the vane blades


208


. As the bulk material conveying areas register with the airlock material outlet


210


, the bulk material falls out of the registered conveying areas and is entrained with the airstream


230


.

FIG. 2

further illustrates a conventional discharge apparatus


220


extending below the airlock


202


. In particular, an intermediate conduit


225


extends below and is attached to the airlock


202


. The airstream


230


passes through an inlet conduit


222


and through an air inlet


224


. The air inlet


224


directs the airstream


230


in a direction substantially parallel with the axis


207


of the axle


204


. The air inlet


224


does not direct the inlet airstream


230


into the airlock material outlet


210


and also does not direct the inlet airstream


230


in a direction toward an area (e.g., a bulk receiving area) defined by the airlock


202


. At most, after the airstream


230


passes through the air inlet


224


, a portion of the inlet airstream


230


may defuse up into the airlock material outlet


210


wherein bulk material is entrained in the airstream


230


, after which the airstream


230


directs the material through the air outlet


228


and into the outlet conduit


226


for discharging.




However, material tends to accumulate in stagnant spaces of the airlock discharge assembly


200


in use. Material also tends to accumulate between the air inlet and outlet, particularly at a point approximately ⅔ of the overall length from the air inlet


224


. Material build up of this manner is discussed in “Pressure Drop Across a Pneumatic Conveying Feeding Tee”,


Pneumatic Conveying


, by H. H. Ottermann and S. J. Meijers, Vol.5, No.1, (March, 1993) pp.27-30.





FIG. 3

illustrates yet another conventional airlock discharge assembly


300


including an airlock


302


having a rotor


303


. The rotor


303


comprises an axle


304


with an axis


307


. A hub


306


is mounted to the axle


304


for rotation therewith and vane blades


308


are attached to an outer surface of the hub


306


and extend radially therefrom. Bulk material areas are defined between adjacent vane blades


308


, a portion of the outer surface of the hub


306


extending between proximate ends of the blade vanes


308


, an interior surface of the housing


305


extending between distal ends of the vane blades


308


and side portions of the housing


305


extending between lateral sides of the vanes


308


. As further shown in

FIG. 3

, a conventional discharge apparatus


320


is provided for discharging bulk material from the bulk material conveying areas. As also shown in

FIG. 3

, an air inlet


324


is provided in a side wall of the housing


305


allowing an airstream


330


to be directly injected into the bulk material conveying areas between the vane blades


308


similar to the embodiment described previously in FIG.


1


.




In use, bulk material enters the airlock discharge assembly


300


through an airlock material inlet


312


and is received into exposed bulk material conveying area(s). The rotor


303


continues to rotate until the bulk material conveying area(s) are registered with the air inlet


324


and the air outlet


328


. An air inlet stream


330


passes through the inlet conduit


322


attached to the sidewall of the housing


305


and is directed substantially parallel to the axis


307


of the axle


304


and directly into one or more bulk material conveying area(s) from a lateral side of the bulk material conveying area(s). Bulk material is entrained into the airstream


330


and then exits through an air outlet


328


provided in a bottom wall of the housing


305


. It is also known to install a circular knife at the air outlet


328


for wear resistance. The bulk material is then discharged with the airstream


330


through an outlet conduit


326


.




The arrangement of components in the airlock discharge assembly


300


, however, still causes high stress in the vane blades


308


when objects become lodged in the air outlet


328


. Moreover, uneven wear of the vane blades


308


at the distal ends occur. Higher blade wear is typical at the distal ends of the vane blades


308


which pass over the air outlet


328


.




SUMMARY OF THE INVENTION




Accordingly, it is an object of the present invention to obviate problems and shortcomings of conventional airlock discharge assemblies. More particularly, it is an object of the present invention to provide airlock discharge assemblies capable of discharging bulk material from an airlock.




Other objects of the invention are to reduce wear and friction on an airlock discharge assembly, and/or to maximize air velocities so that the airflow may impart energy more efficiently to bulk material in an airlock discharge assembly for any given amount of airflow.




Another object of the invention is to provide an airlock discharge assembly adapted to substantially prevent accumulation of portions of bulk material as the material is conveyed through the airlock discharge assembly.




To achieve the foregoing and other objects in accordance with the present invention, discharge apparatus are provided in order to connect to and cover an airlock material outlet. The discharge apparatus include an air inlet adapted to at least substantially direct an airstream through an airlock material outlet and toward an interior area defined by the airlock. The discharge apparatus further include a material directing trough adapted to receive an airstream and bulk material entrained therein from the airlock, and an extension member adapted to at least partially define a path of an airstream.




To further achieve the foregoing and other objects and in accordance with the present invention, an airlock discharge assembly is provided and includes a rotary airlock. The rotary airlock includes a housing having a bulk material inlet and a bulk material outlet. The rotary airlock further includes a central axle within the housing and a plurality of vanes extending in a direction generally away from the central axle wherein adjacent vanes define bulk material conveying areas within the housing. An air inlet is in communication with the housing and is adapted to at least substantially direct an airstream in a direction nonparallel to the axle and toward a bulk material conveying area in communication with the bulk material outlet.











Still other objects and advantages of the present invention will become apparent to those skilled in the art from the following description wherein there are shown and described alternative exemplary embodiments of this invention. As will be realized, the invention is capable of other different, obvious aspects and embodiments, all without departing from the invention. Accordingly, the drawings and descriptions should be regarded as illustrative in nature and not as restrictive.




BRIEF DESCRIPTION OF THE DRAWINGS




While the specification concludes with claims particularly pointing out and distinctly claiming the present invention, it is believed the same will be better understood from the following description taken in conjunction with the accompanying drawings in which:





FIG. 1

is a cross-sectional view of one embodiment of a conventional airlock discharge assembly;





FIG. 2

is a cross-sectional view of another conventional airlock discharge assembly;





FIG. 3

is a cross-sectional view of yet another conventional airlock discharge assembly;





FIG. 4

is a partial sectional perspective view of one exemplary embodiment of the air lock discharge assembly in accordance with the present invention;





FIG. 5

is a perspective view of the discharge apparatus of the airlock discharge assembly illustrated in

FIG. 4

;





FIG. 6

is a partial sectional perspective view of another exemplary embodiment of an airlock discharge assembly in accordance with the present invention;





FIG. 7

is a perspective view of a discharge apparatus of the airlock discharge assembly as shown in

FIG. 6

;





FIG. 7



a


is a perspective view of a discharge apparatus of the airlock discharge assembly as shown in

FIG. 6

illustrating the path of the airstream;





FIG. 8

illustrates a side elevational view of a bulk material discharge assembly in accordance with the present invention;





FIG. 9

illustrates a partial top plan view of the bulk material discharge assembly of

FIG. 8

in accordance with the present invention;





FIG. 10

is a rear elevational end view of the bulk material discharge assembly of FIG.


8


and including a discharge assembly as shown in

FIG. 7

in accordance with the present invention.











DETAILED DESCRIPTION





FIG. 8

illustrates a side elevational view of a bulk material discharge assembly


1000


in accordance with the present invention. The bulk material discharge assembly


1000


may be mounted on a support surface such as a pallet or stand for elevating the assembly


1000


, on a foundation (e.g., a concrete foundation), or directly on a ground surface.




As shown in

FIG. 8

, the bulk material discharge assembly


1000


may also be installed on a trailer


1002


or other transportation device for mobility. In one example, a trailer


1002


may include a chassis


1004


having wheels


1006


for transporting the bulk material discharge assembly


1000


. The trailer


1002


may further include a jack or elevation device


1008


for adjusting the orientation of the bulk material discharge assembly


1000


, or for supporting the trailer


1002


at a desired discharging location and/or orientation. For instance, the jack


1008


may be used to maintain the bulk material discharge assembly


1000


in a substantially horizontal orientation regardless of any irregular surfaces that the trailer is supported on. In addition, the jack


1008


may be extended to elevate the forward portion of the trailer, thereby tipping the bulk material discharge assembly


1000


such that bulk material is encouraged to travel to the rear portion


1028


of a hopper


1012


for distribution.




The trailer


1002


may further include a kingpin


1010


, thereby allowing the trailer


1002


to be transported via a truck (not shown). The bulk material discharge assembly


1000


may include a hopper


1012


for containing bulk materials (not shown) and an engine


1014


(as shown in FIG.


9


), for powering a blower


1016


and a hydraulic pump.




In use, the blower


1016


forces air through conduit


1020


, through an inlet conduit


622


, and into an airlock discharge assembly, for example, airlock discharge assembly


600


as shown in FIG.


8


. Bulk material is then entrained into the airstream and thereafter forced through the outlet conduit, for example, outlet conduit


626


as shown in

FIGS. 9 and 10

.




Entrained, throughout this application, is intended to mean mixing any material in another flowing material to form a heterogeneous or homogeneous mixture. Bulk material may include any material that may be entrained in a flowing material for distribution. For instance, bulk material may comprise composts, chipped woods, chipped barks, mulches, seeds, grains, hays, fertilizers, sands, soils, herbicides, pesticides (e.g., insecticides), plastic pellets, salts or the like. The bulk material may be mixed with other solids and/or liquids prior to, during, and/or after entraining with the flowing material. For instance, mulch may be treated with water before, during and/or after entraining in order to prevent significant diffusing of the mulch into the atmosphere, thereby more efficiently and effectively placing material on a surface in the desired distribution area. In one particular application, a highly pulverized, fine wood mulch material commonly referred to as “black gold” is entrained with air by an airlock discharge assembly and thereafter distributed around trees, bushes, or other landscape terrain. In another example, seed may be mixed with compost and/or fertilizer to encourage seedling growth. In another application, the bulk material may be mixed with solid/liquid herbicides and/or pesticides to deter weed growth and/or protect living organisms (e.g., plants).




When dispensing bulk material, a conduit or pipe, e.g., one or more discharging conduits


1022


may be removed from storage spaces, e.g., storage spaces


1024


as shown in

FIG. 10. A

distal end portion of the discharge conduit


1022


may be connected to the outlet conduit


626


in order to properly direct and discharge the bulk material. Additional discharge conduits


1022


may be linked in series to effectively lengthen the discharge conduit. A plurality of spaces


1024


may be provided to store different sized or a plurality of similarly sized discharge conduits


1022


. In addition, or alternatively, a storage spool


1027


, as shown in

FIG. 8

, may be provided in order to store additional discharge conduits.




The engine


1014


powers a pump that provides a flow of hydraulic fluid from the hydraulic tank


1018


which operates certain functions of the bulk material discharge assembly


1000


. For example, the bulk material discharge assembly


1000


may be provided with an agitator


1026


as best shown in

FIG. 9

which encourages material to travel from the rear


1028


of the hopper


1012


to the front


1030


of the hopper


1012


. The bulk material discharge assembly


1000


may further include a floor conveyor


1032


that encourages movement of the bulk material from the front


1030


of the hopper


1012


to the rear


1028


of the hopper


1012


, towards the discharge assembly


600


.




The bulk material discharge assembly


1000


may further include a vertically operating discharge gate


1034


, as shown in

FIG. 10

, to control the feed of bulk material through a hopper opening


1038


. The bulk material discharge assembly may further include a feed roll


1036


as shown in FIG.


10


. The feed roll


1036


encourages and controls the consistent flow of bulk material entering into the airlock, for instance, into the airlock material inlet


612


of the airlock


600


.




The discharge apparatus according to the invention is adapted to connect to and cover an airlock material outlet, for example, of an airlock


600


. The discharge apparatus comprises an air outlet adapted to at least substantially direct an airstream through an airlock material outlet and toward an interior area defined by an airlock, a material-directing trough adapted to receive an airstream and bulk material entrained therein from the airlock, and an extension member adapted to at least partially define a path of an airstream. In one embodiment, the extension member extends along at least a portion of a length of a material conveying area of an airlock. In a further embodiment, the extension member is arranged in or adjacent a material outlet of an airlock.





FIGS. 4 and 5

depict one exemplary embodiment of an airlock discharge assembly


500


for use with a bulk material discharge assembly


1000


. The airlock discharge assembly


500


includes an airlock


502


, such as a rotary airlock, and a discharge apparatus


520


.




The airlock


502


typically includes a rotor


503


rotatably mounted in a housing


505


. The rotor


503


comprises an axle


504


having an axis


507


, and a hub


506


coupled to the axle


504


for rotation relative to the housing


505


. One or more vanes


508


are typically attached to an outer circumferential surface


509


of the hub


506


such that they extend radially from the hub


506


. The vanes


508


may take the form of tines, brushes, blades, paddles, or the like. The airlock


502


is provided with a material inlet


512


and a material outlet


510


. Typically, the material outlet


510


is a dropout outlet.




In one example, bulk material conveying areas


519


are defined by pairs of adjacent vanes


508


, respectively. The bulk material conveying areas


519


may be further defined by a portion of the outer surface


509


of the hub


506


, and an inner surface portion


513


of the housing


505


. The bulk material conveying areas may be yet further defined by a side wall portion


523


of the housing


505


, or alternatively, by end plates extending between the vanes


508


. Inclusion of end plates may reduce wear of the housing


505


by preventing frictional contact between the bulk material and the side wall


523


of the housing


505


as the rotor


503


rotates about the axis


507


. As shown in

FIG. 4

, the airlock


502


includes a plurality of vanes


508


defining a plurality of bulk material conveying areas


519


. Alternatively, the airlock


502


may include one vane


508


defining a single bulk material conveying area


519


.




One embodiment of a discharge apparatus is illustrated in

FIG. 5

The exemplary discharge apparatus


520


includes a trough


536


provided with an extension member


546


arranged therein. As shown in

FIG. 5

, the extension member effectively raises the bottom of the trough


536


in a portion of the trough. For instance, the extension member


546


may raise the bottom of the trough from about 2 to 6 inches. In another embodiment, the extension member


546


may raise the bottom of the trough from about 3 to 5 inches. In yet another embodiment, the extension member


546


may raise the trough about 4 inches. In one embodiment, the extension member


546


is offset from the bottom of the trough such that the extension member


546


is adapted to be positioned within an interior portion of the airlock discharge assembly


500


.




The extension member


546


is adapted to influence the path of an airstream and reduce a combined cross-sectional area defined by the airlock material outlet


510


and the trough


536


. The extension member


546


may take any form that effectively raises the bottom wall of the trough


536


. For instance, the extension member


546


may take the form of a thin sheet member including a top wall


548


typically spaced from a bottom portion


538


of the trough


536


as best illustrated in FIG.


4


. The extension member


546


may also include an inlet end wall


550


and an outlet end wall


552


. In one embodiment, the end walls


550


,


552


, as shown in

FIGS. 4 and 5

each extend at an angle from the top wall


548


toward the bottom portion


538


of the trough


536


to assist in directing an airstream relative to the discharge apparatus as will be discussed in further detail below. The angles may be the same or different from one another. In one embodiment, each end wall extends outwardly and away from the top wall


548


at identical inclinations.




As shown in

FIG. 4

, the extension member


546


may be formed from thin, rigid material. Alternatively, the extension member


546


may be formed from a thick material or from a solid block disposed, mounted, attached or integrally formed within the trough


536


.




The discharge apparatus


520


may be provided with one or more troughs


536


. In one exemplary embodiment, as shown in

FIGS. 4 and 5

, the trough


536


may be formed separately from the extension member


546


. The extension member


546


may then be disposed, mounted, attached or integrally formed with the trough


536


to effectively raise the bottom wall of the trough as discussed above. For instance, attachment may be provided by a snapping connection, an interference fit, welding, gluing or otherwise attaching the extension member


546


within the trough


536


.




The discharge apparatus


520


may alternatively be formed with one or more extension members


546


in combination with a plurality of troughs. For instance, two troughs may be connected together to form the discharge apparatus


520


, with or without the portions of the trough material located under the top wall


548


of the extension member


546


and between the end walls


550


,


552


. Removing, or failing to provide portions of the trough


536


located under the top wall


548


and between the inlet end wall


550


and the outlet end wall


552


, would save material and reduce the weight of the airlock discharge assembly


500


.




The trough


536


may include a trough sidewall


542


or a plurality of trough sidewalls


542


as shown in

FIGS. 4 and 5

. The trough


536


may also be formed without sidewalls. The trough


536


may further be formed with or without an inlet trough wall


540


. As shown in

FIG. 5

, the trough may be formed without an outlet end wall and, rather, connect directly to a discharging connecter


525


of an outlet conduit


526


. Alternatively, the trough may be provided with an outlet end wall provided with an aperture or opening.




As further shown in

FIGS. 4 and 5

, an inlet conduit


522


may be attached to the inlet trough wall


540


. In one embodiment, an air inlet


524


may be defined by the inlet end wall


550


of the extension member


546


and a portion of the trough


536


. The air inlet


524


may be further defined by the inlet conduit


522


and the inlet trough wall


540


. An outlet conduit


526


may be attached to the opposite end of the trough


536


. The outlet conduit


526


may be formed with a substantially constant cross section throughout its length. However, to facilitate delivery of bulk material, as shown in

FIGS. 4 and 5

, the outlet conduit


526


may include a tapered discharging connector


525


that may funnel or continue to funnel and increase the velocity of the bulk material entering the outlet conduit


526


. The outlet conduit


526


may optionally further include a conduit with a substantially constant cross section


527


for discharging the bulk material to a desired location.




The trough


536


may also comprise upper flanges


544


for attaching the discharge apparatus


520


to the airlock


502


. The discharge apparatus


520


may be attached with screws, rivets, fasteners, vibration dampening fasteners, adhesives, welding, or otherwise attached. Alternatively, the flanges


544


may be part of the housing


505


of the airlock


502


.




In use, bulk material is fed into the airlock discharge assembly


500


through the airlock material inlet


512


. The bulk material enters and at least partially fills one or more of the bulk material conveying area(s)


519


. The bulk material is conveyed by rotating with the rotor


503


about the axis


507


until the bulk material conveying area(s)


519


are registered with the airlock material outlet


510


. An airstream


530


enters the inlet conduit


522


and is directed by the air inlet


524


through the airlock material outlet


510


and toward an interior area (e.g., the bulk material conveying area(s)


519


which are in communication with the outlet


510


) of the airlock


502


. The bulk material located in the bulk material conveying area(s)


519


may be immediately entrained in the airstream


530


. Portions of the bulk material may also fall from the bulk material conveying area(s)


519


into the airlock material outlet


510


and then become entrained in airstream


530


. In one application, a majority of the bulk material is entrained in the airstream


530


as the airstream passes through the bulk material conveying area. The airstream


530


, with the bulk material entrained therein, then exits the bulk material conveying area(s)


519


, as will be described in further detail below.




As illustrated in

FIGS. 4 and 5

, the air inlet


524


is adapted to at least substantially direct an airstream


530


through an airlock material outlet


510


and toward an interior area (e.g., bulk material conveying area(s)


519


) defined by the airlock


502


. In one exemplary embodiment, the air inlet


524


is further adapted to direct a majority of the airstream into a first area


511


of a bulk material conveying area


519


. The bulk material is entrained in the fluid flow as the airstream


530


travels within the air lock


502


and the trough


536


. As the airstream


530


exits the outlet


510


, it directs the material back down into the trough


536


and then into the outlet conduit


526


. In one example, the outlet conduit includes the tapered discharging connector


525


connected to the conduit


527


having a substantially constant cross-section. The tapered discharging connector


525


funnels or continues to funnel the bulk material into a smaller cross-sectional area, thereby increasing the velocity of the airstream


530


and bulk material entrained therein. The inlet end wall


550


and the outlet end wall


552


may be provided to block off a portion of the trough, thereby forcing the material to travel over the top wall


548


. If provided, the end walls


550


,


552


may be angularly oriented relative to the top wall


548


such that they form trapezoidal inclines to allow the airstream and any bulk material entrained therein to ramp up through the airlock material outlet


510


and toward an interior portion (e.g., the bulk material conveying area(s)


519


) of the airlock


502


. Furthermore, the extension member


546


may be offset in the trough


536


such that the inlet end wall


550


is closer to the air inlet


524


than the outlet end wall


552


relative to the air outlet


528


. Offsetting the extension member


546


provides more area at the outlet end of the discharge apparatus


520


thereby helping to prevent occlusion.





FIGS. 6 and 7

depict another exemplary embodiment of an airlock discharge assembly


600


for use with a bulk material discharge assembly


1000


. The airlock discharge assembly


600


comprises an airlock


602


, such as a rotary airlock, and a discharge apparatus


620


. The airlock


602


is similar to the airlock


502


in that it comprises a rotor


603


including an axle


604


having an axis


607


with a hub


606


disposed on the axle


604


. The rotor


603


may include one or more vanes


608


attached to an outer surface


609


of the hub


606


and extending radially from the hub


606


. As in the embodiment of

FIGS. 4 and 5

, vanes


608


may take the form of tines, brushes, blades, paddles, or the like.




In one example, similar to the embodiment of

FIGS. 4 and 5

, bulk material conveying areas


619


are defined by a pair of vanes


608


, and may also be defined by a portion of the outer surface


609


of the hub


606


, and an inner surface portion


613


of the housing


605


. The bulk material conveying areas


619


may be yet further defined by a side wall portion


623


of the housing


605


, or alternatively, by end plates or members extending between the vanes


608


. Inclusion of end plates may reduce wear of the housing


605


by preventing frictional contact between the bulk material and the side wall


623


of the housing


605


as the rotor


603


rotates about the axis


607


. The airlock


602


may include one vane


608


defining a single bulk conveying area


619


. Alternatively, as shown in

FIG. 6

, the airlock


602


may include a plurality of vanes


608


defining a plurality of bulk material conveying areas


619


.




The discharge apparatus


620


includes an extension member


646


. In one embodiment, the extension member


646


may be a portion of the housing


605


of the airlock


602


. Alternatively, the extension member


646


may be formed separately from the airlock


602


and attached to the airlock


602


by any suitable connector, including, but not limited to rivets, bolts, screws, glue, or welding.




In one embodiment, the extension member


646


may take the form of a plate or other member which is not an integral portion of the housing


605


. For example, as shown in

FIGS. 6 and 7

, the plate can extend substantially along an extension plane


645


. As shown, the plate can include a first side


646




a


facing away from the axle


604


and a second side


646




b


facing toward the axle


604


. The plate can also include and end


646




c


that is attached to the material-directing trough


636


. The extension member


646


may also be provided with an aperture


647


in fluid communication with an inlet conduit


622


. For example, as best shown in

FIGS. 6

,


7


and


10


, an end


622




a


of the inlet conduit


622


is positioned adjacent the first side


646




a


of the plate such that the inlet conduit


622


is in fluid communication with the aperture


647


. An airstream


630


can therefore pass through the aperture


647


from the first side


646




a


to the second side


646




b


of the plate. The aperture


647


in combination with the inlet conduit


622


form an air inlet


624


which directs an airstream


630


at least substantially through an airlock material outlet


610


and toward an interior area (e.g., bulk material conveying area(s)


619


) defined by the airlock


602


. The airstream


630


with bulk material entrained therein travels within the interior portion of the airlock


602


until it encounters the end trough


636


.




The end trough


636


is connected to the extension member


646


by any suitable connector(s). In one embodiment, the end trough


636


is pivotally connected to the extension member


646


via a hinge


652


. The hinge


652


may be formed as a living hinge such as a single or multiple piece(s) of flexible plastic fabric, metal, or other material, or may be formed as a leaf hinge or the like. Allowing relative pivoting between the extension member


646


and the end trough


636


permits the end trough


636


to be rotated away from the airlock


602


, thereby allowing maintenance of the interior of the airlock discharge assembly


600


. For instance, bulk material that is lodged or clogged in the air outlet


628


could be easily removed by rotating the end trough


636


to an open position.




The end trough


636


may include one or more walls. In one embodiment, the end trough


636


may include end wall


639


, for example, positioned at an acute angle with respect to the plane of the extension member


646


to prevent accumulation of portions of the bulk material in stagnant areas of the end trough


636


. The end trough


636


may further comprise at least one trough side wall


642


, for instance, two opposing sidewalls


642


as shown in

FIG. 7. A

bottom wall


638


may further be provided to extend between the trough end wall


639


and the air outlet


628


. In one embodiment, an outlet conduit


626


is attached to the trough side wall(s)


642


and the bottom portion


638


.




In one particular embodiment, the end wall


639


is angled to optimize the air flow relative to the discharge apparatus and thereby optimize the distribution of bulk material. The outlet end wall


552


of the discharge apparatus


520


may be angled in a similar manner.

FIG. 7



a


illustrates the discharge apparatus


620


arranged relative to a sidewall of the housing


605


of the airlock


602


. An exemplary plane


658


represents the effective area within the airlock


602


oriented in a direction perpendicular to the airstream


630


. The plane


658


typically remains substantially constant until it reaches the point of deviation


660


. At this point, the effective area is continually or substantially continually reduced until it reaches the conduit


627


having a constant cross section. In one example, the effective area of the plane


658


adjacent the air inlet


624


is approximately 65 square inches and remains approximately 65 square inches along the extension member


646


until reaching the point of deviation


660


.




Once the point of deviation


660


is reached, the effective area of the airflow is reduced, for instance continuously or substantially continuously reduced, from the point of deviation


660


until the airflow reaches the air outlet


628


. In this region, the effective areas of the planes perpendicular to the flow are defined by the ramped trough end wall


639


, the bottom portion, the sidewall of the housing


605


portions of the rotor


603


, and other portions of the housing


605


. Once the airstream passes through the air outlet


628


, the tapered discharging connector


625


continues to gradually reduce the flow area perpendicular to the airstream until reaching the conduit


627


with contact cross section. The conduit


627


may have a cross-sectional area of about 20 square inches.




Gradual reduction of cross-sectional areas is desirable to assist in imparting energy to the bulk material and to prevent settling of portions of the bulk material. The gradual reduction of area gradually increases the velocity of the entrained material which reduces conduit pulsation and material build-up. The embodiment of the airlock discharge assembly


500


also gradually reduces area and therefore increases the velocity in a similar manner.




In an embodiment having an end trough


636


that pivots relative to the extension member


646


, a latch may be provided on the flanges


644


, or elsewhere, to allow selective disengagement of the flanges


644


from the housing


605


of the airlock


602


.




In use, bulk material is fed into the airlock discharge assembly


600


through the airlock material inlet


612


. The bulk material enters and at least partially fills one or more of the bulk material conveying area(s)


619


and is then conveyed by rotating with the rotor


603


until the bulk material conveying area(s)


619


are registered with the airlock material outlet


610


. The bulk material located in the bulk material conveying area(s)


619


may be immediately entrained in the airstream


630


. Portions of the bulk material may also fall from the bulk material conveying area(s)


619


into the airlock material outlet


610


and then become entrained in the airstream


630


. In one application, a majority of the bulk material is entrained in the airstream


630


as the airstream passes through the bulk material conveying area. The airstream


630


, with the bulk material entrained therein then exits the bulk material conveying area(s)


619


as described more fully below.




As illustrated in

FIGS. 6 and 7

, the air inlet


624


is adapted to at least substantially direct an airstream through the airlock material outlet


610


and toward an interior area (e.g., bulk material conveying area(s)


619


) defined by the airlock


602


. On one embodiment, the air inlet


624


is also adapted to direct a majority of the airstream into a first area


611


of the bulk material conveying area


619


. In another embodiment, the air inlet


624


directs the airstream at essentially a right angle relative to the axle


607


of the airlock


602


. The bulk material is entrained in the fluid flow as the airstream


630


travels within the air lock


602


. The airstream


630


directs the material along the length of the extension member


646


and then drops into the end trough


636


. The airstream


630


further carries the material into the outlet conduit


626


. Similar to the embodiments of

FIGS. 4 and 5

, the outlet conduit includes a tapered discharging connector


625


connected to the conduit


627


having a substantially constant cross-section. The tapered discharging connector continues to funnel the airstream


630


, with the bulk material entrained therein, into a smaller cross-sectional area, thereby increasing the velocity of the airstream


630


as described more fully above.




The foregoing description of the various embodiments of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, this invention is intended to embrace all alternatives, modifications and variations that have been discussed herein, and others that fall within the spirit and broad scope of the claims.



Claims
  • 1. An airlock discharge assembly, comprising:a) a rotary airlock comprising a housing having a bulk material inlet and a bulk material outlet, a central axle within the housing and a plurality of vanes extending in a direction away from the central axle, wherein adjacent vanes define bulk material conveying areas within the housing, and wherein the bulk material conveying areas are adapted to register with the bulk material outlet; b) a material-directing trough in communication with the bulk material outlet and adapted to receive an airstream and bulk material entrained therein; c) an extension member including a plate extending at least substantially along an extension plane, wherein the plate includes an end attached to the material-directing trough and is adapted to at least partially define a path of an airstream, the plate including a first side facing away from the axle and a second side facing toward the axle, and the plate is provided with an aperture that extends through the plate from the first side of the plate to the second side of the plate; and d) an inlet conduit including an end positioned adjacent the first side of the plate and in fluid communication with the aperture such that an airstream passes through the aperture from the first side of the plate to the second side of the plate; wherein the aperture in combination with the inlet conduit form an air inlet in communication with the housing and adapted to at least substantially direct an airstream in a direction nonparallel to the axle and toward a bulk material conveying area in communication with the bulk material outlet.
  • 2. The airlock discharge assembly of claim 1, wherein the plate comprises a portion of the housing and extends between the air inlet and the materia-directing trough.
  • 3. The airlock discharge assembly of claim 2, wherein the material-directing trough includes a trough end wall extending at an angle from the portion of the housing and wherein the airlock discharge assembly further comprises an outlet conduit connected at an end of the material-directing trough opposite the trough end wall.
  • 4. The airlock discharge assembly of claim 1, wherein the air inlet is adapted to direct a majority of an airstream into a first area of the bulk material conveying area and the material-directing trough is adapted to receive an airstream with bulk material entrained therein from a second area of the bulk material conveying area.
  • 5. The airlock discharge assembly of claim 4, wherein the first area and the second area are at opposite end portions of the bulk material conveying area.
  • 6. The airlock discharge assembly of claim 1, further comprising an outlet conduit attached to the material-directing trough, the outlet conduit including a tapered discharging connector adapted to funnel bulk material.
  • 7. The airlock discharge assembly of claim 1, wherein the air inlet is adapted to direct a majority of an airstream into the bulk material conveying area in a direction substantially toward the central axle.
  • 8. The airlock discharge assembly of claim 1, wherein the airlock discharge assembly is included as part of a bulk material discharge assembly comprising a hopper defining an interior for storing bulk material, the hopper being provided with a hopper opening, and wherein the bulk material inlet is adapted to receive bulk material from the interior of the hopper.
  • 9. The airlock discharge assembly of claim 1, wherein the end of the plate is pivotally attached to the material-directing trough.
  • 10. The airlock discharge assembly of claim 1, further comprising an outlet conduit, wherein one end of the material-directing trough is attached to the outlet conduit.
  • 11. An airlock discharge assembly, comprising:a) a rotary airlock comprising a housing including an upper end and a lower end, a bulk material inlet located adjacent the upper end and a bulk material outlet located adjacent the lower end, a central axle within the housing and a plurality of vanes extending in a direction away from the central axle, wherein adjacent vanes define bulk material conveying areas within the housing, wherein the bulk material conveying areas are adapted to register with the bulk material outlet to discharge all material and air received by the rotary airlock through the bulk material outlet located adjacent the lower end in use; b) a material-directing trough in communication with the bulk material outlet for receiving bulk material from the bulk material conveying areas as they register with the bulk material outlet; c) an inlet conduit for introducing an airstream to the airlock discharge assembly; and d) an air inlet in communication with the housing and adapted to direct the entire airstream from the inlet conduit in a direction nonparallel to the axle and toward a bulk material conveying area in communication with the bulk material outlet.
  • 12. The airlock discharge assembly of claim 11, further comprising an extension member adapted to at least partially define a path of an airstream.
  • 13. The airlock discharge assembly of claim 12, wherein the extension member is disposed in the material-directing trough.
  • 14. The airlock discharge assembly of claim 13, wherein the extension member comprises a top wall spaced from a bottom portion of the material-directing trough, an inlet end wall and an outlet end wall, each of the end walls being attached at corresponding end portions of the top wall and extending toward the bottom portion.
  • 15. The airlock discharge assembly of claim 14, wherein each of the end walls extends at an angle from the top wall of the extension member toward the bottom portion of the material-directing trough.
  • 16. The airlock discharge assembly of claim 14, wherein the air inlet is defined by the inlet end wall of the extension member and a portion of the material-directing trough.
  • 17. The airlock discharge assembly of claim 16, wherein the air inlet is further defined by an inlet conduit and an inlet trough wall.
  • 18. The airlock discharge assembly of claim 12, wherein the extension member extends between the air inlet and the material-directing trough.
  • 19. The airlock discharge assembly of claim 12, wherein the extension member comprises a plate.
  • 20. The airlock discharge assembly of claim 19, wherein the material-directing trough is attached to one end of the plate.
  • 21. The airlock discharge assembly of claim 20, wherein the end of the plate is pivotally attached to the material-directing trough.
  • 22. The airlock discharge assembly of claim 12, further comprising an outlet conduit, wherein one end of the material-directing trough is attached to the outlet conduit.
  • 23. The airlock discharge assembly of claim 11, wherein the airlock discharge assembly is included as part of a bulk material discharge assembly comprising a hopper defining an interior for storing bulk material, the hopper being provided with a hopper opening, and wherein the bulk material inlet is adapted to receive bulk material from the interior of the hopper.
  • 24. The airlock discharge assembly of claim 19, wherein the plate is provided with an aperture and wherein an inlet conduit is in fluid communication with the aperture.
  • 25. An airlock discharge assembly, comprising:a) a rotary airlock comprising a housing having a bulk material inlet and a bulk material outlet, a central axle within the housing and a plurality of vanes extending in a direction away from the central axle, wherein adjacent vanes define bulk material conveying areas within the housing, and wherein the bulk material conveying areas are adapted to register with the bulk material outlet; b) an air inlet in communication with the housing and adapted to at least substantially direct an airstream in a direction nonparallel to the axle and toward a bulk material conveying area in communication with the bulk material outlet; and c) a material-directing trough in communication with the bulk material outlet and adapted to receive an airstream and bulk material entrained therein, wherein the material-directing trough is pivotally attached to a portion of the discharge assembly.
  • 26. The airlock discharge assembly of claim 25, wherein a plate extends between the air inlet and the material-directing trough.
  • 27. The air discharge assembly of claim 26, wherein the material-directing trough is pivotally attached to the plate.
  • 28. The airlock discharge assembly of claim 26, further comprising an inlet conduit, wherein the plate is provided with an aperture, wherein the inlet conduit is in fluid communication with the aperture, and wherein the air inlet is defined by the aperture and inlet conduit.
  • 29. The airlock discharge assembly of claim 25, wherein the air inlet is adapted to direct a majority of an airstream into a first area of the bulk material conveying area and the material-directing trough is adapted to receive an airstream with bulk material entrained therein from a second area of the bulk material conveying area.
  • 30. The airlock discharge assembly of claim 29, wherein the first area and the second area are at opposite end portions of the bulk material conveying area.
  • 31. The airlock discharge assembly of claim 25, wherein the airlock discharge assembly is included as part of a bulk material discharge assembly comprising a hopper defining an interior for storing bulk material, the hopper being provided with a hopper opening, and wherein the bulk material inlet is adapted to receive bulk material from the interior of the hopper.
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Entry
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