Abstract:
A viscous material container evacuator comprises: a chamber to hold a container and a plunger axially and slidably accommodated within the chamber to express material from the container; at least one hinged enclosure that closes to define the chamber and to securely enclose the container; at least one hydraulically activated fastener that secures the enclosure around the container; a hydraulic motor operatively part of the fastener; and a relief cartridge controllably mounted with a hydraulic line to the motor to deliver a hydraulic drive pressure to the motor and comprising a bypass line around the motor and a pressure sensor to sense a pressure level of the hydraulic drive pressure and to divert the hydraulic drive pressure from the motor when the pressure level is sensed.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The invention relates to a hydraulic system and method, in particular for controlling a fastener for a container evacuator that evacuates silicone gum or other viscous material from a drum to a compounding system. 
         [0002]    In a compounding system, a viscous material is fed to a processing line where feed is mixed and additives are injected in proportions to produce a customized product. The feed material for these processes can be delivered in various containers. When delivered, the material must be removed from the container for processing. For example, a compounding system can require emptying material such as silicone gum from drums or similar containers. However, the feed material may be very viscous and resistant to flow and hence, resistant to removal from the delivery container. 
         [0003]    Some container emptying processes use a plunger to drive through the container content to express the content for further processing. A considerable amount of pressure is needed in these processes to express a viscous material such as a silicone gum. The high expressing force exposes the materials container to very high mechanical stress. For reasons of weight and expense, the containers are usually designed with very thin walls and a structure that is just sufficient to avoid damage to the container during transport. The container is not designed to withstand stress imposed during an emptying operation and the high pressure developed during the emptying operation can easily burst a container structure. 
         [0004]    Reinforcing split metal sleeves or half-shells can be placed around a container during an emptying operation to provide some structural integrity and resistance to bursting. However, the mounting and closing off of the sleeves and half-shells can be very complicated operations, requiring considerable manual labor. The sleeve or half shells are particularly vulnerable to bursting where they are fastened together. Another disadvantage is that the sleeves or half-shells must be adapted in an exact manner to the outside container dimensions thus sometimes requiring an inventory of sleeves or half-shells to accommodate various sized containers. 
         [0005]    Commonly assigned and copending patent application Knox et al., Ser. No. 11/536,700, filed Sep. 29, 2006 and entitled FASTENER FOR A VISCOUS MATERIAL CONTAINER EVACUATOR AND METHOD teaches a secure enclosure for a viscous material container evacuator and method to remove viscous material from a delivery container to a processing system. The viscous material container evacuator comprises: a chamber to hold a container and a plunger axially and slidably accommodated within the chamber to express material from the container; at least one hinged closure that closes to define the chamber and to securely enclose the container; and at least one motor activated fastener that secures the closure around the container. However, while the motor activated fastener is advancement, the fastener is only as secure a closure for the chamber as its particular activating mechanism. Accordingly, there remains a need to provide an activating mechanism for a fastener to securely close a viscous material container evacuator 
       BRIEF DESCRIPTION OF THE INVENTION 
       [0006]    The invention provides a hydraulically driven activating mechanism for a fastener to securely close a viscous material container evacuator. The invention can be described as a viscous material container evacuator, comprising: a chamber to hold a container and a plunger axially and slidably accommodated within the chamber to express material from the container; at least one hinged enclosure that closes to define the chamber and to securely enclose the container; at least one hydraulically activated fastener that secures the enclosure around the container; a hydraulic motor operatively part of the fastener; and a relief cartridge controllably mounted with a hydraulic line to the motor to deliver a hydraulic drive pressure to the motor and comprising a bypass line around the motor and a pressure sensor to sense a pressure level of the hydraulic drive pressure and to divert hydraulic drive pressure from the motor when the pressure level is sensed. 
         [0007]    In an embodiment, the invention is a method to secure an enclosure of a viscous material container evacuator, comprising applying a hydraulic force to drive a fastener shaft against a closure of a material extracting apparatus to enclose a container within the evacuator; sensing the hydraulic force as the fastener is driven; comparing the sensed hydraulic force to a set point; and terminating applying the hydraulic force when the compared sensed hydraulic force is substantially the same as the set point. 
         [0008]    In another embodiment, the invention is a viscous material processing system comprising: a viscous material feed system comprising: a chamber to hold a container and a plunger axially and slidably accommodated within the chamber to express material from the container; at least one hinged enclosure that closes to define the chamber and to securely enclose the container; at least one hydraulically activated fastener that secures the enclosure around the container; a hydraulic motor operatively part of the fastener; and a relict cartridge controllably mounted with a hydraulic line to the motor to deliver a hydraulic drive pressure to the motor and comprising a bypass line around the motor and a pressure sensor to sense a pressure level of the hydraulic drive pressure and to divert the hydraulic drive pressure from the motor when the pressure level is sensed; and a viscous material compounding system that receives material expressed from the feed system. 
         [0009]    In another embodiment, the invention is a viscous material feed system comprising: a container evacuator comprising a chamber to hold a container and a plunger axially and slidably accommodated within the chamber to express material from the container; at least one hinged enclosure that closes to define the chamber and to securely enclose the container; at least one hydraulically activated fastener that secures the enclosure around the container; a hydraulic motor operatively part of the fastener; and a relief cartridge controllably mounted with a hydraulic line to the motor to deliver a hydraulic drive pressure to the motor and comprising a bypass line around the motor and a pressure sensor to sense a pressure level of the hydraulic drive pressure and to divert the hydraulic drive pressure from the motor when the pressure level is sensed; a feed tube that receives material expressed from a container by the container evacuator; and a cutting apparatus that meters material from the feed tube to a processing system. 
         [0010]    In still another embodiment, the invention is a viscous material feed method, comprising: placing a viscous silicone gum containing drum into a material extracting apparatus; securing enclosure of the material extracting apparatus around the drum by applying a hydraulic force to drive a fastener shaft against a closure of a material extracting apparatus to enclose a container within the evacuator; sensing the hydraulic force as the fastener is driven; comparing the sensed hydraulic force to a set point; and terminating applying the hydraulic force when the compared sensed hydraulic force is substantially the same as the set point; and evacuating viscous material from the drum by driving a plunger through the drum to express the silicone gum a viscous material compounding process. 
         [0011]    In another embodiment, the invention is a viscous material container evacuator, comprising: a chamber to hold a container and a plunger axially and slidably accommodated within the chamber to express material from the container; at least one hinged enclosure that closes to define the chamber and to securely enclose the container; at least one motor activated fastener that secures the enclosure around the container; and a hydraulic system that powers the motor, comprising a hydraulic pressure supply, and a relief cartridge that controls the pressure supply to activate the motor by diverting pressure supply from the motor when a set point pressure is attained. 
         [0012]    And in another embodiment, the invention is a method of controlling a battery of hydraulically operated fasteners to a viscous material container evacuator, comprising: setting a set point pressure for each fastener of the battery; supplying an activating hydraulic fluid, pressure to each fastener; and diverting the applied pressure from each fastener as the set point for that fastener is attained. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         [0013]      FIG. 1 ,  FIG. 2  and  FIG. 3  are schematic representations of a material processing system; 
           [0014]      FIG. 4  and  FIG. 5  are perspective views of a drum press; 
           [0015]      FIG. 6  is a cut away view of a section of a drum press; 
           [0016]      FIG. 7  is a perspective view of a hinged enclosure with enclosure door fasteners; 
           [0017]      FIG. 8  is an exploded view of a fastener and hydraulic motor; 
           [0018]      FIG. 9  is an exploded view of a misalignment coupling; 
           [0019]      FIG. 10  is a schematic perspective cut away view of an open fastener; 
           [0020]      FIG. 11  and  FIG. 12  are cut away views of a closed fastener and a fastener in an overrun condition; 
           [0021]      FIG. 13  is a schematic perspective view of a hydraulic motor; and 
           [0022]      FIG. 14  is a diagram of fastener hydraulics. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0023]    The invention relates to the handling of a viscous material such as a silicone gum. “Silicone gum” includes a viscous silicone or polysiloxane or organopolysiloxane that has the chemical formula [R 2 SiO] n , where R=organic groups such as methyl, ethyl, and phenyl. These materials typically comprise an inorganic silicon-oxygen backbone ( . . . —Si—O—Si—O—Si—O— . . . ) with attached organic side groups, which can be four-coordinate. In some cases, organic side groups can be used to link two or more of these —Si—O— backbones together. 
         [0024]    By varying the —Si—O— chain lengths, side groups, and crosslinking, silicones can be synthesized with a wide variety of properties and compositions. They can vary in consistency from liquid to gel to rubber to hard plastic. Silicone rubber or silicone gum is a silicone elastomer, typically having high temperature properties. Silicone rubber offers resistance to extreme temperatures, being able to operate normally from minus 100° C. to plus 500° C. In such conditions tensile strength, elongation, tear strength and compression set can be superior to conventional rubbers. 
         [0025]    A silicone gum can be extruded or molded into custom shapes and designs such as tubes, strips, solid cord or custom profiles within size restrictions specified by a manufacturer. Cord can be joined to make “O” Rings and extruded profiles can also be joined to make up seals. 
         [0026]    It is desirable to provide a viscous teed system that accurately and efficiently processes viscous materials such as silicone gum for use in various applications. However, these materials can be highly resistant to flow, highly adhering, highly cohering, and/or shear thickening and consequently difficult to handle. Accuracy of a packaging process and/or accuracy of a process of obtaining a defined quantity of such material, for example in a continuous process, is costly when substantial time is required for cutting or separating of a quantity of the material from a larger quantity. Also, it is costly and disadvantageous when an incorrect amount of material is used in a downstream process. 
         [0027]    The material is delivered to a viscous feed system in a container such as a drum. Then, the material is removed from the drum for processing. However, the viscous nature of the material makes removal difficult, particularly where removal of a quantified portion is desired for accurate feed to a processing system. A material evacuation process is one procedure for removing material from a container. In this procedure, a platen is driven through the material container to force its contents to express out of the container. A material evacuation process exerts substantial force against a container wall, which can result in frequent container rupture. Both the evacuator and any fastener to evacuator enclosures must be robustly capable of securing enclosure against the substantial force. 
         [0028]    The invention provides a secure closure with a fastener that can with stand high forces exerted on a container wall during material evacuation. The fastener can include a hydraulic motor that drives a lock mechanism that includes a threaded shaft and a clamp block with a nub and a threaded channel that accepts the threaded shaft. The motor drives the threaded shaft to foreshorten the distance between a first closure tug and a lug on a second closure or on the evacuator wall to enclose the container for evacuation. Also, an embodiment of the fastener addresses problems of misalignment between the drive shaft and threaded shaft that arise on account of part tolerance divergence and operational wear. 
         [0029]    Features of the invention will become apparent from the drawings and following detailed discussion, which by way of example without limitation describe preferred embodiments of the invention. In this application, a reference to “back” means left on a drawing or drawings and a reference to “forward” means right on the drawing or drawings. 
         [0030]    A preferred invention embodiment shown in the drawings illustrates the invention as a process to compound silicone gum into a base for forming articles. In the drawings,  FIG. 1  is a schematic top view representation and  FIG. 2  is a schematic side view representation of a material processing system  10  showing an integrated feed system  12  and compounding system  14 . The feed system  12  includes a battery of material extracting apparatus (MEA)  16 , conveyor  18  and chute  20 .  FIG. 4  and  FIG. 5  are elevation views of the MEA  16  and  FIG. 6  is a cut away side sectional view of a section of the MEA  16 . The. MBA  16  includes container evacuator  22 , feed tube  24 , cutting apparatus  26  and floor scale  28 . The integrated feed system  12  is controllably connected to controller  30 .  FIG. 6  is a cut away view of an upper section of the drum press of  FIG. 4  and  FIG. 5 . As shown in  FIG. 1 ,  FIG. 2  and  FIG. 3 , compounding system  14  includes mixer  32 , roil mill  34 , conveyor belt  36  and compounder  38 . 
         [0031]    The MEA  16  serves to express the viscous material from a container to the compounding system  14 . In typical operations, 55-gallon steel drums from a pallet are dumped into totes and the totes (approx. 80 pounds each) are dumped into a Banbury mixer. However, manually maneuvering drums from pallets can cause back and shoulder strains and injuries. In a preferred compounding operation of the invention with respect to  FIG. 1 ,  FIG. 2  and  FIG. 3 , operation commences with delivery of a pallet  40  of four drums  42  of gum. While the container can be any material holding enclosure, the drawings embodiment is a feed system including a method of evacuating a silicone gum-containing drum. A suitable drum  42  in the embodiment, has full openable ends and has a cylindrical wall of steel, fiberboard or other material structure for transporting a silicone gum material. The drum  42  has opposite ends, each of which is openable to accommodate a movable plunger at one end as hereinafter described. 
         [0032]    The material in the drums  42  may be identical or it may be of a variety of physical properties such as viscosity. The drums  42  are removed from the pallet  40  one by one by drum hauler  44  such as from Easy Lift Equipment Co., Inc., 2 Mill Park Court, Newark, Del. 19713. The lid of each of three drums  42  is removed and each of the drums  42  is loaded by the hauler  44  into a respective container evacuator  22 , which may be a Schwerdtel S 6-F drum press. Use of the drum hauler  44  eliminates ergonomic risks associated with lilting and handling the heavy drums  42 . The silicone gum is then forced from each drum in measured aliquots by the MEA  16  into the conveyor  18 . In the drawings embodiment, the MEA  16  comprises a container evacuator  22 , feed tube  24  and cutting apparatus  26 . The container evacuator  22  can be a drum press, which is a device that evacuates viscous or compacted contents from a drum. As illustrated in  FIG. 2  and  FIG. 3 , the container evacuator  22  is a press that comprises a substantially cylindrical chamber  50  with hinged enclosures  52  and  54  for securing a drum  42  removably within the chamber  50 . The chamber  50  and hinged enclosures  52  and  54  securely cradle the drum  42  during a material extracting operation. A disc-shaped platen  56  fits into the chamber  50  with a flat driving surface  58  oriented perpendiculars to the longitudinal axis of the chamber  50  and correspondingly perpendicular to the longitudinal axis of a drum  42  held within the chamber  50 . 
         [0033]    The operation of feed system  12  can be described with reference to  FIG. 1 ,  FIG. 2 ,  FIG. 4 ,  FIG. 5  and  FIG. 6 . In operation, the press enclosures  52  and  54  are unlatched by activating fasteners  110  to open enclosures  52  and  54 . The drum hauler  44  is used to load a first drum  42  into the press cavity  60 . The drum  42  is positioned by a locator ring  62  at the base  64  of the chamber  50 . The press enclosures  52  and  54  resist axial expansion pressure exerted by plunger  72  driving through drum  42 . The enclosures  52  and  54  are secured by a plurality of fasteners  110 , which are described in detail with reference to  FIGS. 7 to 10  and which are driven by a hydraulic motor  224  as hereinafter described in detail with reference to  FIGS. 4 to 5  and  7  to  14 . 
         [0034]      FIG. 7  is a perspective view of hinged enclosures  52  and  54  secured with fasteners  110 . The fasteners  110  serve to clamp and align the hinged enclosures  52  and  54  as described hereinafter.  FIG. 8  is an exploded perspective view of one fastener  110  including hydraulic motor  224  with drive shaft  114 . From left back to front forward, fastener  110  comprises misalignment coupling  116 , restart spring pin  118 , restart spring  126 , drive tube  120 , threaded shaft  122 , drive housing  124  and clamp block  132 . Threaded shaft  122  has a splined reduced diameter back section  158 , a threaded middle section  160  and a forward reduced diameter plane section  162 . A back face  164  is directed toward the drive shaft  114  and a forward face  166  is directed toward a threaded channel  168  of clamp block  132 .  FIG. 10  and  FIG. 11  show lugs  128  and  130  as respective sections of hinged enclosures  52  and  54 . 
         [0035]    Misalignment coupling  116  serves to transmit mechanical power from one rotating shaft to another where the shafts are not in exact alignment. in  FIGS. 8 to 11 , the misalignment coupling is shown transmitting mechanical power from drive shaft  114  to threaded shaft  122 . In  FIG. 9 , misalignment coupling  116  is a three section part including back couple half  134  and forward couple half  136  and coupler section  138 . Each couple half  134  and  136  has a configured interior that forms a continuous passageway  140  with coupler section  138 . Coupler section  138  has hack keys  142  and forward keys  144  that nest respectively into complementary keyways  146  of back couple half  134  and keyways  148  of forward couple half  136 . Connector  134  has retaining groove  150  and forward couple half  136  has retaining groove  152  and the couple halves  134  and  136  are retained by respective retaining rings  154  and  156 . The keyways  146  and  148  with inserted keys  142  and  144  and retaining rings  154  and  156  loosely connect each couple half  134  and  136  with the coupler section  138 . 
         [0036]    Back couple half  134  interior passageway  140  has an inner cylindrical splined surface  170  adapted to receive a complementary splined surface  172  of drive shaft  114  and forward couple half  136  has a splined surface  174  adapted to receive the complementary splined surface of reduced diameter back section  158  of threaded shaft  122 . The  172 ,  158  splined surfaces are configured and oriented to nestle within respective spline surfaces  170 ,  174  in an interdigitated manner. The term interdigitated means that the splines are interlaced as fingers of two hands can be joined in parallel. 
         [0037]    Coupler section  138  interior passageway  140  portion has a smooth wall and this portion of the passageway  140  has a larger diameter than back couple half or forward couple half diameters defined by grooves of the splined surfaces  170  and  174 . The coupler section  138  connects the halves  134 ,  136  so that the spline configurations of the halves  134 ,  136  are misaligned to trap the drive shaft  114  and threaded shaft  122  to one another. The keys  142  and  44  are held by rings  154  and  156  with some degree of axial play and are placed 90° out of phase to one another to provide a slackened tolerance to both axial and angular misalignment between drive shaft  114  and threaded shaft  122 . The misalignment coupling  116  configuration transmits drive shaft torque while accommodating axial and angular misalignment. 
         [0038]      FIG. 10  is a schematic cut away view of an open fastener  110 ;  FIG. 11  is a cut away side view of a closed fastener  110 ; and  FIG. 12  is a schematic cut away side view of a fastener  110  in an overrun condition. With reference to  FIGS. 5 through 12 , a method of securing the hinged enclosures  52  and  54  comprises activating hydraulic motor  224  to cause drive shaft  114  to drive connected threaded shaft  122  into complimentary threaded channel  168  of clamp block  132 . Clamp block  132  is a bracket shaped piece with threaded channel  168  at a back bracket end  180  and a biasing structure shown as nub structure  184  with nub  186  at a forward bracket  182  end. In operation, the threaded shaft  122  threads through threaded channel  168  and a forward face  166  of the shaft  122  imposes upon a first lug  128  of enclosure  52 . Clamp block  132  is connected with drive housing  124  via mounting pin  188  and snap rings  190  through drive housing  124  opening  192  and aligned slot  194  of clamp block  132  (and securing lug  128  through its hole  198 ). And, drive housing  124  is connected to the motor  122  through drive tube  120  by means of fasteners  196  ( FIG. 8 ). So as the motor  224  advances the threaded shaft  122 , the shaft  122  in turn draws clamp block  132  (via the motor  224  to drive tube  120  drive housing  124  to clamp block  132  connection) to foreshorten a distance between the nub  186  until the nub  186  imposes against lug  130  of enclosure  54 . The nub  186  is tightened by action of the threaded shaft  122  to bind the lugs  128 ,  130  to form a powerful hydraulic driven enclosure of the MEA  16  around a drum  42  within the MEA chamber  50 . 
         [0039]    An overrun backoff mechanism is another embodiment illustrated in  FIGS. 10 through 12 . Restart pin  118  and a restart spring  126  are shown in  FIGS. 8 and 10  through  12 .  FIG. 10  illustrates an open fastener  110  showing the threaded shaft  122  substantially but not completely unthreaded from threaded channel  168 . The restart pin  118  and restart spring  126  are imposed into a passage  178  of the threaded shaft  122  longitudinal axis. The  FIG. 10  shows the restart pin  118  biased by the drive shaft  114  against the threaded shaft  122  but with travel remaining within the passage  178 .  FIG. 11  shows the lock fully closed with the restart pin  118  advanced against the fully compressed restart spring  126  imposing against the threaded shaft  122  passage  118  end. The restart pin  118  pushes (biases) on the threaded shaft  122  to cause it to fully extend and to reengage the clamp block. Then in an overrun condition as shown in  FIG. 12 , the threaded shaft unthreads itself from the clamp block  132 . 
         [0040]    Another embodiment of the invention relates to hydraulic control of fasteners  110 . In  FIG. 4 ,  FIG. 5  and  FIG. 7 , each hydraulic motor  224  has a relief cartridge  218  with hydraulic line  240  connected to a hydraulic pump  242 . The hydraulic line  240  transmits hydraulic pressure from pump  242  to each hydraulic motor  224  of each fastener  110 . An exemplary hydraulic motor  224  with relief cartridge  218  and hydraulic line ports  212  and  214  is illustrated in  FIG. 13  and schematically represented in  FIG. 14 . 
         [0041]      FIG. 14  is a diagram of a hydraulic system  216  that includes matching cartridges  218 ,  220  and  222  that are respectively associated with motors  224 ,  226  and  228 .  FIG. 4 ,  FIG. 5 ,  FIG. 7  and  FIG. 14  illustrate a hydraulic system  216  that includes hydraulic line  202  that serves the hydraulic motors, first providing hydraulic drive pressure to motor  224  and then returning hydraulic fluid from the battery of motors  224 ,  226  and  228  via hydraulic return line  204 . Each hydraulic motor  224 ,  226  and  228  includes respectively, relief cartridge  218 ,  220  and  222 . The system  216  is driven by pump  232  and controlled by tandem spool valve  230 , which in turn is controlled by controller  30 . 
         [0042]      FIG. 14  shows a four way, three position tandem spool valve  230 . In an open position, hydraulic fluid flows from port P to port A and port B to port T. This results in hydraulic fluid flow from each port C to port D of each motor  224 ,  226  and  228 . In an exemplary operation, output torque of motor  224  correlates to a differential pressure across the motor  224 . When the differential reaches a set point, relief cartridge  218  terminates motor  224  rotation by diverting the hydraulic fluid flow through the next relief cartridges  220  and  222 . Similarly, differential is sensed and flow through each respective motor  226  and  228  is terminated when the set point is reached. When a set point for all motors  224 ,  226  and  228  is reached, the three corresponding fasteners ( 110  in  FIG. 4 ,  FIG. 5  and  FIG. 7 ) are in an open position to permit access to the container evacuator chamber  50 . In an embodiment, the set point is stored and pressure is evaluated with a controller  30  that may be a PLC and pressure transmitter combination. 
         [0043]    With additional reference to  FIG. 10 ,  FIG. 11  and  FIG. 12 , hydraulic fluid flow into port B and out of port A of hydraulic motor  224  causes threaded shaft  122  to rotate unscrewing itself from clamp block  132 . This causes clamp block  132  to extend. Once clamp block  132  has extended to the point that clamp block  132  comes into contact with lug  128 , as illustrated in  FIG. 10 , clamp block  132  is at its end of travel and can extend no further. If the hydraulic motor continues to run, threaded shaft  122  will continue unscrewing itself from clamp block  132 . With no travel left for the clamp block  132 , threaded shaft  122  will travel toward hydraulic motor  224 , compressing restart spring  126  between restart spring pin  118  and the threaded shaft  122 . The threads on threaded shaft  122  will eventually disengage from clamp block  132  ( FIG. 12 ). With the threads of the threaded shaft  122  disengaged from clamp block  132 , continued rotation of threaded shaft  122  will cause no further travel in either threaded shaft  122  or clamp block  132 . 
         [0044]    In an overrun situation, hydraulic fluid flows into port A and out of port B of hydraulic motor  224  causing rotation of threaded shaft  122  in its tightening direction. Restart spring  126  presses on threaded shaft  122  pushing its threads into the threaded bore of clamp block  132  causing the threads to engage. Once the threads of clamp block  132  and threaded shaft  122  have engaged, threaded shaft  122  will travel toward lug  128 . Threaded shaft  122  will come in contact with lug  128  ( FIG. 10 ). At this point clamp block  132  will begin to retract. Once nub  186  comes into contact with lug  130 , the torque required to rotate the threaded shaft  122  will increase. Because the pressure differential from port A and B of hydraulic motor  224  correlates to output torque, the pressure drop across ports A to B of hydraulic motor  224  correspondingly increases. As described hereinafter, a maximum torque can be limited by controlling a maximum hydraulic pressure drop from port A to B of hydraulic motor according to a relief cartridge  218  set point. 
         [0045]    In a fastener unlocking cycle, a solenoid of the spool valve  230  directs fluid flow from port P to port B and from port A to port T resulting in hydraulic flow from port C to port D in each motor  224 ,  226  and  228 . Flow from port C to port D actives each motor  224 ,  226  and  228  to open each respective fastener  110 . When an open situation is determined by PLC timing, the PLC returns the valve  230  to neutral. In an event that a motor fails to operate when hydraulically activated, relief valve  232  prevents pressure from increasing above a “damage pressure.” 
         [0046]    Again with reference to  FIGS. 1 through 6 , each MEA  16  includes the container evacuator  22 , feed tube  24  and cutting apparatus  26  and each is set on a respective floor scale  28 . In each MEA  16 , the feed tube  24  is connected through the disc shaped platen  56  to communicate with the press cavity  60 . The platen  56  is driven by hydraulic plunger  72 . An operator can commence system operation at controller  30 . When a cycle is activated by an operator, a plunger  72  of each container evacuator  22  of the battery shown in  FIG. 1  is activated via control lines  74 . Then, as the screw conveyor  18  starts turning, the press platen  56  with connected feed tube  24  is forced by hydraulically driven plunger  72  to travel down into the drum  42  interior. As further illustrated in  FIG. 6 , as platen  56  traverses the drum  42  longitudinal axis within the press cavity  60 , drum contents are displaced upward into a connecting orifice  68  of the feed tube  24 . As the platen  56  completes traversing the drum axis, all material is forced upward into the feed tube  24  to be eventually expelled from the feed tube discharge port  70 . 
         [0047]    The material is cut into small pieces by cutting apparatus  26  as it exits from the discharge port  70  to the conveyor  18  to charge to compounding system  14 . Cutting can be accomplished by various cutting mechanisms, including a cutting head disposed at an outlet end of the feed tube. For example, Brandi, U.S. Pat. No. 5,797,516, incorporated hereto in its entirety discloses a cutting head formed by a knife that is detachably mounted in an axial direction and radial and tangential to the axial direction. The cutting head is situated relative to a feed tube about a common central longitudinal axis. 
         [0048]    In the  FIG. 4 ,  FIG. 5  and  FIG. 6  embodiment, the MEA  16  includes a cutting apparatus  26  located at discharge port  70 . The cutting apparatus  26  includes rails  80  that secure cutting wire  82  to guide the wire  82  to cut material exiting the feed tube discharge port  70 . The rails  80  secure the cutting wire  82  to traverse the feed tube  24  longitudinal axis at discharge port  70  when activated by controller  30  via lines  84  and  86  ( FIG. 1 ). 
         [0049]    The controller  30  of  FIG. 1  illustrates an embodiment of the invention. Controller  30  is responsively connected to loss of weight scales  28  via tines  92  to sense loss of weight as material is expressed from the drums  42  to conveyor  18 . The controller  30  computes a weight charged of material charged to the conveyor  18  by the difference between an initial weight of the MEA  16  and initially emplaced and full drum  42 . In the embodiment of the drawings, the controller  30  can sense an initial total weight of all the MEAs  16  and emplaced full drums  42  of the MEA battery of for example, the three shown in  FIG. 1 . The controller  30  monitors the combined weight as material in the drums is evacuated to the conveyor  18 . The controller  30  contemporaneously calculates a weight of material charged to the conveyor  18  and hence to the compounding system according to a difference between the initial total weight and contemporaneously sensed total weight. 
         [0050]    The controller  30  also controls operation of cutting apparatus  26  according to the calculated charged material weight. Initially, the cutting apparatus  26  can be programmed to make cuts of about “football” sized material, for example to fit into a 14″ inner diameter screw conveyor  18 . Once a piece of material is cut from the feed tube discharge port  70 , floor scale  28  senses a contemporaneous weight and feeds this signal back to the controller  30 . When the controller  30  senses a contemporaneous weight signal and calculates that a total charged weight is within a specified range of total material to be charged (for example within 15 pounds of “set point”) to the compounding system  14 , the controller can signal the cutting apparatus  26  via lines  84  to increase cut frequently to produce smaller “diced” pieces. The smaller diced pieces at approach to set point permit improved control of teed to attain a charged material weight within a prescribed tolerance range, for example +/−2 pounds for a batch. 
         [0051]    As the drum  42  evacuation process is completed, door fasteners of the hinged enclosures  52  and  56  open and a controller  30  Run Screen displays “NEW DRUM.” A beacon light mounted on the container evacuator  22  turns yellow, indicating the drum  42  is ready to be changed. The chamber  50  hinged enclosures  52  and  56  open the hydraulic unit motor terminates. The door fasteners  110  open and the empty drum is removed, typically with the drum hauler. The evacuator  22  is reloaded with a drum and the process repeated. 
         [0052]    As material is charged from the MEAs  16  to the screw conveyor  18 , the conveyor is turning at low rpms to feed the material to the mixer. The screw is programmed to stop turning 90 seconds after the last MEA  16  makes its last cut. This time can be adequate to clear all material from the conveyor  18 . 
         [0053]    Conveyor  18  transports and drops the cut silicone gum to chute  20  to compounding system  14 , which includes mixer  32  such as a Banbury, roll mill  34 , conveyor belt  36  and compounder  38 . The material dropped from chute  20  may be a feed of silicone gums of varying physical properties such as varying viscosity. In the mixer  32 , fumed silica, the silicone gum and a treating agent can be added to form a densified polymer/filler mass. After the gum feed is mixed, it is dropped into the nip  46  of roll mill  34  where the material is rolled into a strip form. After a drop, a programmed logic controller (PLC), for example controller  30  verifies that the mixer drop door has opened, then reclosed and is ready for feed. For any residual material that hangs in the chute, a “pusher” is programmed to sweep a few seconds after the conveyor  18  stops. This serves to scrape down the chute  20 , and ensure all material gets into the mixer  32  to correctly formulate the batch. 
         [0054]    The mill imparts a final mix to fully incorporate filler and to cool material. Then, the material is stripped from the mill a strip form. The strip form is fed by means of conveyor belt  36  into compounder  38 , which may be an extruder. The compounder  38  serves to clean and form the material for packaging. The material can be packaged and boxed through an automated cut, weigh and packaging system. 
         [0055]    The feed system and method of the invention can be used in conjunction with a process to compound a silicone rubber into a base for sealing compounds with additives such as pigments dosed to the rubber in appropriate quantities and mixed in large mixers or extruders.  FIG. 1  illustrates an exemplary process wherein a filler such as finned silica is continuously treated and compounded with a silicone polymer such as a vinyl-terminated polydimethylsiloxane. 
         [0056]    The following Example is illustrative and should not be construed as a limitation on the scope of the claims. 
       Example  
       [0057]    This EXAMPLE is a combined description of press (MEA) experiments at Schwerdtel US headquarters (New Jersey), ProSys Corporation (Missouri), and at GE Silicones Waterford, N.Y. Experiments on the shaftless screw conveyor were conducted at GE Silicones Waterford using Martin Sprocket equipment. 
         [0058]    A viscous material feed system as schematically illustrated in the drawings included a Schwerdtel S 6-F drum press mounted to Vishay BLH floor scale that measured material flow according to loss of weight. The Schwerdtel S-6F press included a hydraulic pressure driven cylinder and platen that drives a platen into the 55 gallon drum. 
         [0059]    The feed system included a feed tube to receive material expressed from a drum by the press and a pneumatic solenoid operated cutting system that metered material from the feed tube to a 12″×24′ shaftless screw conveyor according to loss of weight sensed by the scale. The screw conveyor interfaced to a chute. The chute permitted material to fall via gravity directly to a Banbury mixer. Material remaining in the chute was cleared by a pneumatic pusher prior to each mix (GE design and fabrication). The system was controlled by operators at two (2) QuickPanel LM90 touch screens. 
         [0060]    In operation, an operator first entered set points into a system controller. One set point represented a target batch of silicone gum to be charged to a Banbury mixer, which was part of a silicone gum compounding system. A pallet of four (4) fifty-five (55) gallon drums of polymer (Viscosity Range 150,000 to 900,000 Poise) was placed on a drum carousel. The 55-gallon straight-sided steel drums were delivered by the carousel and one drum was loaded into the Schwerdtel S 6-F drum press using an Easy Lift Equipment Drum Hauler unit. The Schwerdtel S 6-F drum press was controlled by a GE Fanuc 90/30 PLC. Material was displaced, from the drum to the feed tube by the hydraulic Schwerdtel gum press. 
         [0061]    The operator pressed a START OR RESTRT BATCH button of the controller to commence operation. The press doors were secured by hydraulically driven fasteners. Then, as the screw conveyor started turning, the hydraulically driven press platen commenced traveling down into the drum. As platen traversed the drum, drum contents were squeezed upward into the feed tube. As the platen completed traversing the drum axis, all material was forced upward into the feed tube. As material exited the feed tube, a pneumatic solenoid operated cutting system diced the material into pieces that then fell into a 12″×24′ shaftless screw conveyor to charge to a Banbury mixer. 
         [0062]    A batch of material flow from conveyor to the Banbury mixer was measured by loss of weight detected by the Vishay BLH load cells. A combined weight of presses, feed tubes, cutting mechanisms and material-containing drums was registered by the control system as a first weight. The control system monitored a charged weight of silicone gum to the Banbury by registering progressing weight as silicone gum was pressed from the drums and expelled through the feed tubes and cutting systems. The control system displayed a differential between the first weight and registered progressive weights that represented a charged silicone gum weight. As the charged silicone gum weight was within 15 pounds of the set point, the 
         [0063]    A system operator observed the differential weight and terminated the batch operation when the differential weight registered within a ±2 pound range of the set point, the pneumatic solenoid operated cutting system rate was increased to dice smaller aliquots of exiting material. The batch feed operation was terminated by the operator when the control system registered a charged silicone guru weight with 2 pounds of the set point. 
         [0064]    The EXAMPLE illustrates control of material charge to a compounding system according to a feed system that is secured by fasteners according to the invention. 
         [0065]    The invention includes changes and alterations that fall within the purview of the following claims. The foregoing examples are merely illustrative of the invention, serving to illustrate only some of the features of the present invention. For example, the invention includes a controller with a set of instructions: to refer to a look-up data base to determine a set point for a material to be charged to a compounding system; sensing an initial combined weight of a material extracting apparatus and a container with material; signaling commencement of the material extracting apparatus operation to evacuate the material from the container; sensing a progressing combined weight of the material extracting apparatus and the container with material; calculating a charged material weight according to a difference between the initial combined weight and the sensed progressing combined weight; and terminating the material extracting apparatus operation when a calculated charged material weight is within a specified range of the set point. 
         [0066]    The appended claims are intended to claim the invention as broadly as it has been conceived and the examples herein presented are illustrative of selected embodiments from a manifold of all possible embodiments. Accordingly it is Applicants&#39; intention that the appended claims are not to be limited by the choice of examples utilized to illustrate features of the present invention. 
         [0067]    As used in the claims, the word “comprises” and its grammatical variants logically also subtend and include phrases of varying and differing extent such as for example, but not limited thereto, “consisting essentially of” and “consisting of.” 
         [0068]    Where necessary, ranges have been supplied, those ranges are inclusive of all sub-ranges there between. Such ranges may be viewed as a Markush group or groups consisting of differing pairwise numerical limitations which group or groups is or are fully defined by its lower and upper bounds, increasing in a regular fashion numerically from lower bounds to upper bounds. It is to be expected that variations in these ranges will suggest themselves to a practitioner having ordinary skill in the art and where not already dedicated to the public, those variations should where possible be construed to be covered by the appended claims. 
         [0069]    It is also anticipated that advances in science and technology will make equivalents and substitutions possible that are not now contemplated by reason of the imprecision of language and these variations should also be construed where possible to be covered by the appended claims. 
         [0070]    All United States patents (and patent applications) referenced herein are herewith and hereby specifically incorporated by reference in their entirety as though set forth in full. 
         [0071]    The invention includes changes and alterations that fall within the purview of the following claims.