Patent Document

TECHNICAL FIELD  
       [0001]     The present disclosure pertains to material handling, and more particularly, to an apparatus and methods to transfer powder in the form of microspheres from a large storage container to a smaller container.  
       BACKGROUND  
       [0002]     Phenolic powder, may be received as a fragile, low bulk density hollow powder which is composed of microspheres in a thermoplastic resin form. It is desirable to carbonize the microspheres by placing the powder into graphite containers and then treating the containers and material by extreme heating. The microspheres which are 15-150 microns in diameter before and after the heat treatment process. The carbonized microspheres have a variety of uses. For example, they may be used as the basis of a low density insulating material. The hollow phenolic powder is not considered a free flowing material because of its low-bulk density and if aerated or fluidized, the hollow pehnolic powder may exhibit packing or caking.  
         [0003]     Handling this phenolic powder is dangerous because its composition is a high density exothermic material which is easily combustible. In fact, the material may spontaneously smolder at relatively low temperatures. Typically, such materials are transported in standard 55 gallon drums. Presently, such materials are manually loaded from the drum into a smaller graphite container for use in the heat treatment step in order to process the material as explained above. The powder must be protected in order to prevent caking or packing which could damage the utility of the microspheres. The transfer of such powder from a 55 gallon drum is dangerous because microsphere dust is created in the transfer process. Such dust is combustible and creates a hazard for employees responsible for the transfer of the powder from the drum to process machinery. Moreover, powder dust generated from the transfer is essentially wasted material. Since the powder is expensive, such waste is undesirable.  
         [0004]     Moreover, the powder is fragile and must be protected during the transfer process. Since the powder is susceptible to clotting, the flow of the powder from the drum to the process machinery may cause clogging of the conduits, making it difficult to transfer the powder to the processing machinery. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0005]      FIG. 1  is a perspective view of an example apparatus to transfer phenolic powder shown with the drum in a lowered position.  
         [0006]      FIG. 2  is a side view of the example transfer apparatus of  FIG. 1  shown with the drum in the raised loading position.  
         [0007]      FIG. 3  is a side view of the example transfer apparatus of  FIG. 1  shown with the rotating arm in an unloading position and the drum placed in a raised, inverted position.  
         [0008]      FIG. 4  is a view of the example transfer apparatus from the drum loading door with the drum in the lowered position.  
         [0009]      FIG. 5  is a view of the dust hood work station and piping to the dust collector of the example transfer apparatus in  FIG. 1 . 
     
    
     DETAILED DESCRIPTION  
       [0010]     While the present invention is capable of embodiment in various forms, there is shown in the drawings and will hereinafter be described a presently preferred embodiment with the understanding that the present disclosure is to be considered as an exemplification of the invention, and is not intended to limit the invention to the specific embodiment illustrated.  
         [0011]     An example transfer apparatus  10  is illustrated in  FIGS. 1-5 . The illustrated transfer apparatus  10  includes a drum dumper  12 , a work station  14  and a dust collector  16 . The example apparatus  10  of  FIG. 1  allows the transfer of phenolic powder in the form of hollow microspheres from a storage container which may be a typical 55 gallon steel drum such as drum  18  which is held by the drum dumper  12  to the work station  14 . Of course, persons of ordinary skill in the art will appreciate that other types of storage containers may be used with the apparatus  10 . The drum dumper  12  and the work station  14  are surrounded by a safety enclosure  20  which includes an access door  22  and a drum door  24  to protect users from the moving parts of the drum dumper  12  as explained below. The enclosure  20  includes a control box  26  and a controller hood  28 . Persons of ordinary skill in the art will appreciate that the apparatus  10  may be used to transfer other types of materials such as any free flowing hazardous or non-hazardous powders or granules.  
         [0012]     The drum dumper  12  has a base  30  which is mounted on a pair of skids  32  and  34 . The base  30  mounts a support housing  36  which encloses the electrical and hydraulic machinery (not shown) for the components described below. The support housing  36  has a side wall  38  with an access port  40  with various hydraulic supply lines  42 . The base  30  also has a lift  44  on which the drum  18  is held. The lift  44  has a loading pad  46  which accommodates the bottom of the drum  18 . The lift  44  has a pair of side walls  48  and  50  which extend vertically and serve to constrain the movement of the drum  18  on the pad  46 . The lift  44  has a pair of track members  52  and  54  which traverse a pair of guides  56  and  58  mounted respectively on a pair of support arms  60  and  62  to move the drum  18  vertically from a lower position for initial placement of the drum  18  to a higher, raised position as shown in  FIG. 2  for the unloading operation. The lift  44  is powered by hydraulic pressure, but persons of ordinary skill in the art will appreciate that other mechanisms such as electrical motors or pneumatic pressure may be used to operate the lift  44 .  
         [0013]     The drum dumper  12  also has a rotating arm  64  which rotates around a pivot  66  installed on the support housing  36 . The rotating arm  64  is connected to the support arms  60  and  62  and thus rotates the drum  18  from a loading position shown in  FIG. 2  to an inverted unloading position shown in  FIG. 3 . In this example, the rotating arm  64  is rotated by an electrical motor (not shown), although persons of ordinary skill in the art will appreciate that other equivalent actuators such as hydraulics or pneumatic pistons may be used.  
         [0014]     In the illustrated example, each of the support arms  60  and  62  have a horizontal member  67  and  68  respectively which supports a funnel  70 . The funnel  70  has an open end  72  which will accommodate the top of the drum  18  when the drum  18  is raised on the lift  44  as shown in  FIG. 2 .  
         [0015]     The control box  26  of this illustrated example has a start button  74 , a stop button  76  and a dust collector button  78 . Activation of the start button  74  allows power to be supplied to all components. Activation of the stop button  76  cuts off power to all components. As will be explained below, changing the state of the dust collector button  78  starts and stops the dust collector  16 .  
         [0016]     The funnel  70  of the illustrated example has a semi-conical shape with the relatively wide open end  72  and an opposite narrow end  80 . The narrow end  80  is connected to a conduit  82 . As shown in  FIG. 3 , when the support arms  60  and  62  are rotated around the pivot  66 , the drum  18  is inverted and the funnel  70  directs materials from the drum  18  through the open end  72  to the narrow end  80  of the funnel  70 , and then through the conduit  82  to an angled nozzle  84 . The conduit  82  of the illustrated example has a pneumatic iris valve  86  near the narrow end  80  of the funnel  70  allowing control of the flow of materials from the drum  18  to the funnel  70 . Of course, those of ordinary skill in the art will appreciate that other types of valves may be used for the iris valve  86 . The funnel  70  has an air vent port  88  which is connected to a suction hose  90 . The suction hose  90  allows for the removal of dust generated from the removal of an empty or partially emptied drum such as drum  18  from under the funnel  70  to the dust collector  16 .  
         [0017]     As shown in  FIG. 4 , the drum dumper  12  of the illustrated example has an upright position. After the drum  18  is loaded on the lift  44  via the drum door  24 , the drum dumper  12  can be moved into the raised position to fit the top of the drum  18  into the open end  72  of the funnel  70 . A control panel  92  is mounted on the controller hood  28  in the illustrated example. The control panel  92  has an override button  94 . It has additional controls for activating the rotation of the pad  46  between the loading and unloading positions. The controls include a load switch  96  and an unload switch  98 . Those of ordinary skill the art will appreciate that other controls such as, for example, foot pedals may be used to operate the rotation of the arms  60  and  62  and the attached pad  46 .  
         [0018]     After the drum  18  is loaded on the pad  46  with the pad  46  in a lowered position (see, e.g.  FIG. 1 ), the lift  44  is raised to a raised position such as the position shown in  FIG. 2  so the top of the drum  18  is inserted into the open end  72  of the funnel  70 . By activating the unload switch  96 , the drum dumper  12  may be placed in an unloading and inverted position such as the position shown in  FIG. 3  in which the support arms  60  and  62  and lift  44  are rotated until the drum  18  is inverted at an angle from the vertical plane sufficient to allow gravity to pull the materials out of the drum  18 . The contents of the drum  18  then flow out of the drum  18  via gravity through the open end  72  of the funnel  70  to the narrow end  80  out of the nozzle  84 . After the drum  18  is emptied, the drum dumper  12  may be returned to a loading position by activating the load switch  98 . The operation of the drum dumper  12  may be stopped at any point by activating the override button  94 .  
         [0019]     As shown in greater detail in  FIGS. 3 and 5 , the work station  14  of the illustrated example allows a user to control the flow of the powder from the drum  18  to fill one or more processing containers such as a series of storage bins  100 . The storage bins  100  in this example are constructed of graphite for use in heat processing of the powder. As will be appreciated by those of ordinary skill in the art, other types of containers may be used to hold the transferred powder.  
         [0020]     The work station  14  of the illustrated example has a back wall  102  and a pair of side walls  104  and  106  which form a dust hood enclosure  108 . The dust hood enclosure  108  contains a hose  110  for transfer of the powder to the bins  100 . The dust hood enclosure  108  traps dust produced by the transfer of the powder to the bins  100 . Access to the dust hood enclosure  108  is made via an access door  112  which is attached to the enclosure  108  by a hinge  114 . A front wall  116  forms the remainder of the enclosure and shields the bins  100 . The work station  14  of the illustrated example is supported by four legs  118 .  
         [0021]     The work station  14  of the illustrated example also has a bottom panel  120  and a top panel  122 . The top panel  122  has an access opening  124  which is framed by a conduit  126  having an annular mounting surface  128 . The access opening  124  is of sufficient diameter to accommodate the nozzle  84  of the drum dumper  12 . A locking collar  130  is mounted via a series of bolts  132  to the annular mounting surface  128 . The locking collar  130  is coupled to a turbine vibrator  134  which allows the collar  130  to be agitated in an oscillating motion in the access opening  124 . The locking collar  130  and annular mounting surface  128  sandwich a flexible layer  136  which contains an access opening  138 . The flexible layer  136  surrounds the nozzle  84  when the drum  18  is inverted as shown in  FIG. 3  to substantially prevent dust from escaping when the nozzle  84  is inserted into the access opening  124 . The vibrator  134  serves to shake loose any powder which may be clumped in the nozzle  84 . The turbine vibrator is air actuated but other types of vibration devices may be used.  
         [0022]     The access opening  124  forms the wide end of an inverted conical conduit  140 . The opposite narrow end of the conical conduit  140  is attached to the flexible hose  110 . The flexible hose  110  carries the materials from the nozzle  84  to the bins  100  located on the bottom panel  120  of the work station  14 .  
         [0023]     In the illustrated example, a pinch valve  142  is coupled to the end of the flexible hose  110 . The pinch valve  142  has two handles  144  and  146  which allow a user to close the valve  142  and, thus, prevent the flow of material from the inverted conical conduit  140  into the flexible hose  110 . When the storage drum  18  is inverted in the unloading position (e.g. the position shown in  FIG. 3 ), the access opening  124  receives the material from the storage drum  18  and the material passes to the conical conduit  140 .  
         [0024]     As exampled above, the series of empty storage bins  100  are placed on the bottom panel  120  of the work station  14 . A user may open the access door  112  as shown in  FIG. 5  in order to take the flexible hose  110  and move it over the storage bins  100  to fill each individual bin. Once the desired bin or bins  100  have been filled, the pinch valve  142  and/or the iris valve  86  may be shut to cut off the flow of additional powder. The bins  100  may then be removed from the enclosure  108  for further processing. Alternatively, a second door may be located in place of the front wall  116  to allow the bin(s)  100  to be loaded or unloaded into the enclosure  108  via a fork lift or other mechanical device.  
         [0025]     The dust hood enclosure  108  of the illustrated example traps the dust produced by the transfer operation. Those of ordinary skill the art will appreciate that the illustrated apparatus can be modified in other ways to fill the bins  100 . For example, work gloves installed in the walls of the dust hood enclosure  108  could be used to manipulate the hose  110  without opening the access door  112  to ensure a substantially or even totally contained transfer. Alternatively, remote automatic control of the hose  110  using, for example, servo motors coupled to the hose  110  could be used to isolate the transfer of the powder to the bin(s)  100 .  
         [0026]     As shown in  FIGS. 4 &amp; 5 , the back wall  102  of the work station  14  of the illustrated example has upper and lower ventilation slits  150  and  152  which are used to ventilate the dust hood enclosure  108  in order to remove stray dust generated by the transfer process. In addition, the side wall  104  of the illustrated example has a light slit  154  which has a light  156  used to illuminate the dust hood enclosure  108 . The dust hood enclosure  108  has a fire suppression system such as, for example, a pair of sprinkler heads  158  and  160  which are installed on the interior of the top panel  122 . The sprinkler heads  158  and  160  are attached to a fire suppression material supply  162  (shown in  FIG. 5 ) via a piping network  164 . The sprinkler heads  158  and  160  can flood the dust hood enclosure  108  with the fire suppression material (e.g. water or foam) in order to prevent combustion of the powder or dust. The triggering of the sprinkler heads  158  and  160  may be automatically initiated by a temperature sensor or may be manually triggered by the user. As shown in  FIG. 5 , the light  156  may be turned on and/or off via an external switch  166 .  
         [0027]     In the illustrated example, the dust collected from the funnel  70  in the drum dumper  12  and the dust hood enclosure  108  of the work station  14  is contained in a dust collector  16  which is shown in  FIGS. 2, 4  and  5 . A vertical suction pipe  170  has an upper branch  172  and a lower branch  174 . The upper branch  172  is connected via an adaptor  178  to the upper ventilation slit  150  of the back wall  102  and the lower branch  174  is connected via an adaptor  181  to the lower ventilation slit  152  of the back wall  102 .  
         [0028]     The dust collector  16  of the illustrated example is mounted on four support legs  180 . The dust collector  16  has a chamber defined by a front wall  182 , a back wall  184 , and two side walls  186  and  188 . The dust collector  16  also has a top panel  190  and a conically shaped bottom  192 . A blower  194  is mounted on the top panel  190  to create suction force in the chamber to attract dust away from the work station  14  and the funnel  70 . The vertical suction pipe  170  and the suction hose  90  from the funnel  70  are connected to the conical bottom  192  of the dust collector  16 . An exhaust vent  196  extends from the side wall  186  and an air intake  198  extends from the side wall  186 . The air intake  198  provides the blower  194  with a fresh supply of air which is circulated via the exhaust vent  196 . The exhaust vent  196  also serves the purpose as an explosion vent from the chamber of the dust collector  16 .  
         [0029]     In the illustrated example, a pair of sprinkler nozzles  200  and  202  are mounted on the front wall  182  of the dust collector  16  for fire suppression. The sprinkler nozzles  200  and  202  are connected to the piping network  164 . The conical bottom  192  has a collection portal  204  and a pinch valve  206 . As shown in  FIG. 4 , a hose  208  is coupled to the pinch valve  206 . A filter bag  212  lines the chamber of the dust collector  16  which traps the dust from the exhaust vent  196  and the air intake  198 . The blower  194  is activated by pushing the dust collector button  78  on the control box  26  in  FIG. 1 . The blower  194  creates a suction force in the chamber of the dust collector  16  which sucks dust out of the hood enclosure  108  and the funnel  70 . The dust collected in the chamber of the dust collector  16  is trapped in the filter bag  212  and is removed via opening the pinch valve  206  and causing the dust to be sucked out of the hose  208 . The dust thus may be collected and reused by placing a dust container such as a storage drum  214  under conical bottom  192  to be filled with the hose  208 . Alternatively, the dust may be simply removed to a disposal container such as the storage drum  214 .  
         [0030]     Although certain methods and apparatus have been described herein, the scope of coverage of this patent is not limited thereto. On the contrary, this patent covers all apparatus, methods and articles of manufacture fairly falling within the scope of the appended claims either literally or under the doctrine of equivalents.

Technology Category: 7