Abstract:
A spout controls grain or other particulate material falling through and being discharged from a conduit. An array of plates is mounted at the discharge end of a chute to control the flow of the particulate material there from. A counterbalance mechanism is coupled to each of the plates and can be precisely adjusted to provide the appropriate counterbalancing force on the plates to control the particulate material flow without damage to the particulate material and to minimize the dust generated in the flow of the material. A divider is mounted in the stream of material flowing to the array of plates to reduce the dust escaping the flowing material.

Description:
This claims the benefit of U.S. Provisional Patent Application Ser. No. 61/811,339, filed Apr. 12, 2013, which is hereby incorporated by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     Grain and other particulate material falling uncontrolled at high velocities causes: (1) damage to the grain and other particulate material and (2) creates dust. The damage occurs both during fall in a downwardly inclined conduit, as well as upon impact after discharge from the conduit. The damage is apparently caused by particle-to-conduit abrasion and particle-to-particle impact, and these interactions cause fines and dust. 
     The velocity increase of the material is most rapid in a vertical conduit, but even in a slanting conduit, velocities of several hundred feet per minute are attained in a few feet. A free-falling stream of such material tends to reach a terminal velocity because the air currents within and around the stream cause turbulence when the stream is unconfined. Upon discharge, grain or other particulate material flowing in conduits can reach velocities well above such terminal velocities. In a long conduit, the velocity of the stream can exceed even two thousand feet per minute. It is believed that the damaging velocity is not highly dependent on the angulation of the conduit. As such, the damaging velocity is roughly the same for a given stream whether it is falling in a vertical conduit or an angled conduit. 
     For a given type of grain or other particulate material, a velocity of 1600 feet per minute is the approximate damaging velocity in many cases. Damage to the material and creation of dust as the result of high conduit velocities also occurs with materials other than grain, although it is most important in respect to grain because of the relative frangibility and layered structure of grain kernels. 
     To prevent a falling particulate stream of material from exceeding damaging velocity and generating excessive dust, one straightforward approach is to limit the distance of the drop or to angulate the conduit so that the velocity increase is diminished. However, it is difficult to avoid a substantial elevation change in many instances, as for example in loading grain or other particulate material into the hold of a ship. 
     A flow restriction in the path of the falling material may slow the material velocity. This is often achieved by devices called “dead boxes” which have a narrow fixed throat section mounted directly in the conduit. However, dead boxes are effective primarily in those situations where the grain or other particulate material flow rate (i.e., bushels per hour) is constant or within a relatively narrow range so as to avoid “surges.” However, constant velocity is not usually the case. In the typical situation, surges, abrupt changes in flow rate, occur repeatedly. Surging occurs, for example, when a conveyor bucket empties into the upper end of the chute and a period of lower flow may follow, until another bucket refills the chute. Non-uniform moisture content in the grain or other particulate material is another cause of surges. 
     When the flow rate is uneven, the use of a fixed restriction such as a dead box to retard flow is of little effect. In periods of low flow rate, the small stream passes almost unrestrained through the throat opening, but at periods of heavy flow, a “head” of grain or other particulate material builds up rapidly above the throat. This can cause bridging or clogging which can choke off flow completely. 
     In addition to the problem of damage to the grain or particulate material due to high falling velocities, air entrained within the falling stream is a significant problem due to the creation of dust. Ambient dust as a result of a falling stream of particulate material typically requires workers to wear masks or other protective gear. Furthermore, the work environment is clouded by the dust and workers have difficulty seeing for secure footing and evaluation of the level of fill of the vessel receiving the grain or particulate material. 
     Known methods and apparatus attempting to reduce the dust and fall velocity of grain or other particulate material in vertical conduits by which the velocity can be prevented from exceeding the damaging value even under widely varying flow rates are disclosed in U.S. Pat. Nos. 6,085,987 and 4,342,383, each of which is hereby incorporated by reference in its entirety. 
     The devices in each of these cited patents include an array of downwardly and inwardly sloping blades supported by the body of an accumulator. The blades have lower ends which define an opening between them, the opening having an area that at its maximum is substantially smaller than the area of the conduit. The overlapping blades are angled inwardly so that they deflect the grain particles centrally as they fall. The inward deflection of the particles toward the smaller area of the throat causes a mass of grain or other particulate material particles to accumulate above the blades and over the opening in an accumulation chamber within the conduit. 
     Variable biasing means act on the blades to urge them inwardly and the biasing means is responsive to the weight of the accumulated mass of the particles to provide a larger opening as the weight increases, thereby releasing particles more rapidly from the accumulation space above the blades and reducing the area of the opening as the weight of particles decreases. 
     However, the adjustability of the biasing mechanism disclosed in these patents in some instances is inadequate. In an accumulator or regulating device, it is important to keep the biasing force of the blades on the grain or other particulate material flow without applying excessive force to cause the grain or other particulate material to back-up and the accumulation mass above the gate or opening of the blades to grow too large and become clogged or jammed. 
     As such, there is a need for an improved system for regulating the flow of grain or other particulate material that overcomes these and other problems in the art, particularly the excessive generation of dust and damage to the falling grain or other material without creating a blockage of accumulated grain. 
     SUMMARY OF THE INVENTION 
     These and other objectives of this invention have been attained by a spout to control grain or other particulate material falling through and being discharged from a conduit. In one embodiment of this invention, an array of plates is mounted at the discharge end of a chute to control the flow of the particulate material there from. A counterbalance mechanism is coupled to each of the plates and can be precisely adjusted to provide the appropriate counterbalancing force on the plates to control the particulate material flow without damage to the particulate material and to minimize the dust generated in the flow of the material. A divider is mounted in the stream of material flowing to the array of plates to reduce the dust escaping the flowing material. The divider splits the flow of particulate material into at least two split streams and a void region is created below the divider to control the dust. 
     As the grain flows through the chute section and around the divider, it enters a funnel as the split streams are merged together. As the grain exits the funnel, it enters a spout and engages the plates. As the weight of the grain impinges upon the plates, the plates are urged outwardly against the bias of the counterbalance mechanism to increase the open area for the grain to flow through the spout. As the flow of grain decreases, the weight of the grain on the plates likewise decreases and the bias of the counterbalance mechanism springs urges the plates inwardly thereby directing and focusing the flow of the grain through the assembly. Advantageously, the void region proximate the divider entraps the dust and collects it and circulates it back into the split streams of grain thereby minimizing the escape of the dust during the transfer process of the grain through the assembly. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention itself will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein: 
         FIG. 1  is a perspective view of one embodiment of a spout assembly according to this invention; 
         FIG. 2  is a cross-sectional view of the spout assembly of  FIG. 1  with grain flowing through it; 
         FIGS. 3A-3B  are sequential cross-sectional views of grain flowing through a spout of the assembly of  FIGS. 1 and 2 ; 
         FIG. 4  is a side elevational view of the spout assembly of  FIGS. 1-3B ; 
         FIG. 5  is a perspective view of an alternative embodiment of this invention; 
         FIG. 6  is a view of a counter-balance mechanism of the embodiment of  FIG. 5 ; and 
         FIG. 7  is a cross-sectional view taken along line  7 - 7  of the embodiment of  FIG. 5 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to  FIG. 1 , a perspective view of one embodiment of a dustless spout assembly  10  according to this invention is shown. Cross-sectional views of the spout assembly  10  are likewise shown in  FIGS. 2-3B . The assembly  10  includes an upper chute section  12  formed by an upper and a lower chute  14 ,  16  telescopically mated together. While two chutes are shown and described, this invention is not limited to two chutes and only one chute or more than two chutes can be used. The upper chute  14  is received within the lower chute  16  as shown in  FIG. 2 . In one embodiment, the outer perimeter dimension of the lower chute  16  is 23 inches by 23 inches and the similar dimensions of the upper chute  14  are likewise designed to matingly fit within the lower chute  16 . In operation, the spout assembly  10  is adapted for the transfer of grain, corn or other particulate material  18  in a generally vertical downward direction from a supply of grain  18  into a rail car, cargo hold or other receptacle at the downstream exit end of the assembly  10 . 
     The length of the chute section  12  of the assembly  10  is adjustable to accommodate different delivery environments for the grain  18 . In the embodiment shown in  FIGS. 1-3B , the relative positions of the upper and lower chutes  14 ,  16  are telescopically adjustable and this may be accomplished in any one of a variety of manners including a winch  20  mounted to an outer surface of the lower chute  16  as shown in  FIG. 1 . The winch  20  includes a hand crank  22  for manually adjusting a length of a cable  24  attached to the winch  20  on the lower chute  16 . An upper end (not shown) of the cable  24  is attached to the upper chute  14  or another fixed surface positioned above the lower chute  16 . Operation of the winch  20  adjusts the length of the cable  24  and thereby the position of the lower chute  16  relative to the upper chute  14  and a vertical height of the chute section  12 . Alternatively, the chute  16  may be moved vertically up and down depending on the size of the rail car and the means for movement of the chute  16  may be a hydraulic or other appropriate system. Chains  26  with hooks  28  on opposite ends of each chain engage through rings  30  mounted on the outer surface of the chutes  14 ,  16  as shown in  FIGS. 1 and 2  may be utilized to secure the position of the chutes  14 ,  16  relative to each other once adjusted to a desired length. 
     As shown particularly in  FIG. 2 , a divider  32  is positioned centrally within the assembly  10  and in one embodiment in the upper chute  14  to extend longitudinally between opposite sections of the chute  14 . The divider  32  is fixedly mounted within the assembly  10  within the travel path of the grain  18  flowing through the chute section  12  so as to divide the flow of grain  18  into first and second split streams  34   a ,  34   b  of grain on opposite sides of the divider  32 . In one embodiment, the divider  32  may be an angle iron having a pair of generally perpendicularly oriented legs  36   a ,  36   b  with the juncture  38  between the legs oriented medially within the chute section  12  and directed upwardly to thereby divide the flow of grain  18  into the split streams  34   a ,  34   b . The construction and material of the divider  32  may be modified with the respective legs  36  being longer for heavier material flowing through the assembly  10  as is required for a particular application. Moreover, in alternative embodiments of this invention, the position of the divider  32  within the assembly  10  may be adjustable vertically depending upon the desired flow characteristics of the material  18  within the assembly  10 . The divider  32  may be of a different design to shift the stream  34  into more than two split streams within this invention. 
     One advantage that the divider  32  according to various embodiments of this invention is that a region  40  immediately below the divider  32  and generally between the spaced split streams  34   a ,  34   b  of material  18  is a void region with little or no grain within the void region  40 . Due to the flow characteristics of the particulate material  18  and the divider  32  splitting the flow of material into the split streams  34   a ,  34   b , a significant portion of the dust  42  generated from the flow of the material  18  is entrapped within the void region  40  immediately below the divider  32 . As such, the generation of the dust  42  which would normally result from the flow of material  18  is minimized and reduced as it is trapped and concentrated within the void region  40  below the divider  32 . 
     After the split streams  34   a ,  34   b  flow past the divider  32  and downstream from the void region  40 , they merge back together in a funnel  44  mounted beneath the chute section  12 . The funnel  44  includes a pair of opposed tapered sidewalls  46   a ,  46   b  which are aligned longitudinally across the assembly  10  and generally parallel with the orientation of the legs  36   a ,  36   b  and the longitudinal axis of the divider  32 . At the downstream end, narrow portion of the funnel  44 , a spout  48  is mounted to the assembly  10 . The spout  48  has a pair of spaced, generally parallel outer walls  50   a ,  50   b , each of which extends downwardly from one of the sidewalls  46   a ,  46   b  of the funnel  44 . A pair of opposed and moveable plates  52   a ,  52   b  is mounted within the spout  44  to deflect and guide the grain  18  flowing from the funnel  44  into the spout  48  as shown generally in  FIGS. 2-3B . Each plate  52  is an elongate planar member which is mounted by a hinge  54  along its upper edge at the juncture between the spout  48  and the funnel  44 . A longitudinal axis of the divider  32  may be parallel to the longitudinal axes of the plates  52   a ,  52   b . A flange  55  is formed or mounted at the distal end of each plate and orientated perpendicularly to the plane of the associated plate  52 . In one embodiment, the flange  55  is ¼″ key stock. The flanges  55  catch or divert some of the material  18  and assist in movement of the plates  52 . 
     A counterbalance mechanism  56  in the form of one or more compression spring and rod assemblies  58  is mounted adjacent the lower end of each plate  52 . In one embodiment as shown in  FIGS. 2-3B , the counterbalance mechanism  56  includes one or more rod and compression spring assemblies  58  with a rod  60  pivotally attached to an outer surface of the plate  52  and extending laterally outwardly through a hole  62  in the outer wall  50  of the spout  48 . A knob  64  is formed on the terminal end of the rod  60  on the exterior of the spout  48  as shown in  FIGS. 1-3 . A compression spring  66  is mounted between an abutment in the form of a nut  68  threaded on the rod  60  and the inner face of the outer wall  50  of the spout  48 . The compression spring  66  biases the plate  52  toward the center line of the assembly  10  and the opposite plate and into the path of the grain  18  flowing downwardly from the funnel  44  and into and through the spout  48 . 
     In one embodiment, the counterbalance mechanism  56  includes a pair of opposed plates  52   a ,  52   b  with two threaded rod and spring assemblies  58  coupled to each plate  52 . One of ordinary skill in the art would appreciate that the biasing force delivered onto each plate  52  may be adjusted depending upon the strength or spring constant of the spring  66  and the number of springs  66  engaging the plate  52 . In one embodiment of this invention, two 25 pound springs  66  are mounted to each plate  52  producing a 50 pound biasing force on the plate  52  such that over 50 pounds of grain  18  is needed to deflect the plate  52  outwardly and enlarge the open area in the spout  48  for the grain  18  to flow through and over the plate  52 . With the two plates  52   a ,  52   b  arrangement shown in  FIGS. 1-3  and four 25 pound springs  66  mounted to the plates  52 , a total of more than 100 pounds of grain  18  is needed to deflect both of the plates  52   a ,  52   b  outwardly as shown in  FIG. 3B . As a result, the spout assembly  10  of this invention avoids the clogging of excessive accumulation of material  18  even during surges while minimizing the discharge of dust and fines into the work environment. 
     As the grain  18  flows through the chute section  12  and around the divider  32 , it enters the funnel  44  as the split streams  34   a ,  34   b  are merged together. As the grain  18  exits the funnel  44 , it enters the spout  48  and engages the plates  52   a ,  52   b . As the weight of the grain  18  impinges upon the plates  52 , the plates  52  are urged outwardly against the bias of the counterbalance mechanism  56  to increase the open area for the grain  18  to flow through the spout  48  as shown in  FIG. 3B . As the flow of grain  18  decreases, the weight of the grain  18  on the plates  52  likewise decreases and the bias of the counterbalance mechanism springs  66  urges the plates  52  inwardly thereby directing and focusing the flow of the grain  18  through the assembly  10 . 
     Advantageously, the void region  40  entraps the dust  42  and collects it and circulates it back into the split streams  34   a ,  34   b  of grain thereby minimizing the escape of the dust during the transfer process of the grain through the assembly  10 . The opposing ends of the funnel  44  and spout  48  may be capped with opposing end plates  70  as shown in  FIG. 1 . 
     Referring to  FIGS. 5-7 , a second embodiment of a dustless spout assembly no according to this invention is shown. The assembly  110  includes an upper chute section  112 . In operation, the spout assembly  110  is particularly adapted for the transfer of soybeans or other particulate material in a generally vertical downward direction from a supply of soybeans into a rail car, cargo hold or other receptacle at the downstream exit end of the assembly  110 . 
     A funnel  144  is located downstream from the chute section  112  and includes a pair of opposed tapered sidewalls  146   a ,  146   b  and a pair of opposed sidewalls  147   a ,  147   b  to form a rectangular funnel  144 . The tapered sidewalls  146   a ,  146   b  are generally parallel with the orientation of legs  136   a ,  136   b  of a divider  132  mounted in the funnel  144  and in the flow path of the material. At the downstream end, narrow portion of the funnel  144 , a spout  148  is mounted to the assembly  110 . The spout  148  has a pair of spaced, generally parallel outer walls  150   a ,  150   b , each of which extends downwardly from one of the sidewalls  146   a ,  146   b  of the funnel  144 . A back wall  151  is mounted between the outer walls  150   a ,  150   b . A door  153  is opposite the back wall  151  and is pivotally mounted to an edge of the wall  150   b  by one or more hinges  155 . The door  153  may be secured closed by one or more latch assemblies  157 . A port or window  159  may be included in the door  153 . 
     As shown particularly in  FIG. 7 , the divider  132  is positioned centrally within the funnel  144  to extend longitudinally between opposite sections of the funnel  144 . The divider  132  is fixedly mounted within the funnel  144  within the travel path of the soybeans flowing from the chute section  112  so as to divide the flow of soybeans into first and second split streams on opposite sides of the divider  132 . In one embodiment, the divider  132  may have a pair of generally perpendicularly oriented legs  136   a ,  136   b  with the juncture  138  between the legs oriented medially within the funnel  144  and directed upwardly to thereby divide the flow of soybeans into the split streams. 
     One advantage that the divider  132  according to various embodiments of this invention is that a region  140  immediately below the divider  32  and generally between the spaced split streams of material is a void region with little or no material within the void region  140 . Due to the flow characteristics of the particulate material and the divider  132  splitting the flow of material into the split streams, a significant portion of the dust generated from the flow of the material is entrapped within the void region  140  immediately below the divider  132 . As such, the generation of the dust which would normally result from the flow of material is minimized and reduced as it is trapped and concentrated within the void region  140  below the divider  132 . 
     A pair of opposed and moveable plates  152   a ,  152   b  is mounted within the assembly  110  to deflect and guide the soybeans flowing from the funnel  144  into the spout  148  as shown generally in  FIGS. 5-7 . Each plate  152  is a planar member which is mounted by a hinge  154  along its upper edge at the juncture between the spout  148  and the funnel  144 . 
     After the split streams flow past the divider  132  and downstream from the void region  140 , they merge back together in the funnel  144  mounted beneath the chute section  112 . A counterbalance mechanism  156  in the form of one or more compression spring and rod assemblies  158  is mounted adjacent the lower end of each plate  152 . In one embodiment as shown in  FIGS. 5-7 , the counterbalance mechanism  156  includes one or more rod and compression spring assemblies  158  with a rod  160  pivotally attached to an outer surface of the plate  152  and extending laterally outwardly within a housing  163  adjacent to the outer wall  150  of the spout  148 . A compression spring  166  is mounted between an abutment in the form of a brace plate  165  and a nut  168  threaded on the rod  160  and the inner face of the outer wall  150  of the spout  148 . The compression spring  166  biases the plate  152  toward the center line of the assembly  110  and the opposite plate and into the path of the soybeans flowing downwardly through the funnel  144  and into and through the spout  148 . 
     Each spring and rod assembly  158  is mounted within the housing  163  and between one of the plates  152  and a brace plate  165 . A series of nuts  167  are each threaded onto one of the rods  160  and washers  169  may be spaced on the rod  160  and associated spring  166 . The biasing force delivered to the plate  152  may be adjusted in a number of ways. The position of the nut  168  adjacent the plate  165  on the rod  160  may be adjusted to compress or decompress the associated spring  166 . Similarly, the nut  167  on the opposite end of the rod  160  may be adjusted also. Additionally, the position of the brace plate  165  within the housing  163  may be adjusted via mounting bolts  171  securing the brace plate  165  along a slot  173  in the housing  163 . Moreover, springs  166  of different strength and/or spring constants can be used to vary the biasing force on the plates  152 . The biasing force on one plate  152   a  may be adjusted to be different from or the same as the biasing force on the other plate  152   b , as needed. 
     In one embodiment, the counterbalance mechanism  156  includes the pair of opposed plates  152   a ,  152   b  with five threaded rod and spring assemblies  158  coupled to each plate  152 . One of ordinary skill in the art would appreciate that the biasing force delivered onto each plate  152  may be adjusted depending upon the strength or spring constant of the spring  166  and the number of springs  166  engaging the plate  152 , in one embodiment of this invention. As a result, the spout assembly  110  of this invention avoids the clogging of excessive accumulation of material even during surges while minimizing the discharge of dust and fines into the work environment. 
     As the soybeans flow through the chute section  112  and around the divider  132  in the funnel  144  as the split streams are merged together. As the material exits the funnel  144 , it enters the spout  148  and engages the plates  152   a ,  152   b . As the weight of the material impinges upon the plates  152 , the plates  152  are urged outwardly against the bias of the counterbalance mechanism  156  to increase the open area for the material to flow through the spout  148 . As the flow of material decreases, the weight of the material on the plates  152  likewise decreases and the bias of the counterbalance mechanism springs  166  urges the plates  152  inwardly thereby directing and focusing the flow of the material through the assembly  110 . Advantageously, the void region  140  entraps the dust and collects it and circulates it back into the split streams of material thereby minimizing the escape of the dust during the transfer process of the material through the assembly  110 . 
     The invention is described herein for use in controlling the flow of grain, soybeans or other particulate material, and it is readily useful for other materials. The particulate material streams or flows through the assembly and drops directly into the chamber of the cargo carrier below. The cross-sectional area of the opening in the spout may be smaller than the cross-sectional area of the channel section so that a mass of particulate material tends to accumulate at the funnel and above the opening in the spout. The accumulated particulate material mass reduces the velocity of the particulate material without clogging the stream of material. 
     The quantity of particulate material, the variable diameter of the flow stream, the variable speed of the flow or height of drop of the material in addition to the kind of grain or particulate material and the associated weight thereof are factors which may be considered when adjusting the counterbalance mechanism. The counterbalance mechanism provides for a variable biasing force or a resistance upon a downward flow of the particulate material so that the variable input forces available from respective parameters of the particulate material are offset by the variable biasing or reaction forces delivered by the counterbalancing mechanism to the plates. This invention provides a highly sensitive counterbalancing mechanism for acute and precise adjustment based on the proper particulate material flow parameters and operation depending upon the particular type of grain or material. Moreover, one or more features of the assembly, including, but not limited to, the divider, funnel, spout, counterbalance mechanism and plates, contribute to the reduction of dispersed dust and controlled flow of the material. 
     According to another embodiment, a method of retrofitting a conduit through which particulate material flows in a generally downward direction is described. The conduit includes a regulator for controlling the flow of the material therethrough, the regulator includes a plurality of downwardly and inwardly sloping plates having lower ends in the path of the flowing material in the conduit, and the plates slowing the movement of the material and deflecting the material toward a longitudinal axis of the conduit. The method includes coupling a counterbalance mechanism to the plates to deliver a biasing force on the plates inwardly in a direction tending to reduce a size of an opening defined by lower ends of the plates through which the material flows. The method also includes restricting the fall of the material and slowing movement through the opening with the plates. The method also includes dividing the flowing stream into a plurality of split streams. The method also includes adjusting the biasing force delivered by the counterbalance mechanism on the plates. 
     The dividing step may be performed prior to the restricting step. The method may also include delivering the biasing force to the plates through a spring mounted relative to a portion of the counterbalance mechanism for contact with the respective plate. The method may also include adjusting the biasing force delivered to selected ones of the plates without adjusting the biasing force delivered to a remainder of the plates. The biasing force may be adjusted as a function of a spring constant of the spring. 
     From the above disclosure of the general principles of this invention and the preceding detailed description of at least one embodiment, those skilled in the art will readily comprehend the various modifications to which this invention is susceptible. Therefore, I desire to be limited only by the scope of the following claims and equivalents thereof.