Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B24—GRINDING; POLISHING
  • B24C—ABRASIVE OR RELATED BLASTING WITH PARTICULATE MATERIAL
  • B24C3/00—Abrasive blasting machines or devices; Plants
  • B24C3/18—Abrasive blasting machines or devices; Plants essentially provided with means for moving workpieces into different working positions
  • B24C3/26—Abrasive blasting machines or devices; Plants essentially provided with means for moving workpieces into different working positions the work being supported by barrel cages, i.e. tumblers; Gimbal mountings therefor
  • B24C3/263—Abrasive blasting machines or devices; Plants essentially provided with means for moving workpieces into different working positions the work being supported by barrel cages, i.e. tumblers; Gimbal mountings therefor using refrigerating means

Definitions

• the present invention relates to the deflashing art and more particularly to cryogenic deflashing apparatus for the removal of flash in a low temperature environment wherein the flash is embrittled for easy removal by the bombardment of a high velocity pellet media stream.
• prior art throwing wheels have proven incapable of uniformly distributing the media over the desired work surfaces within the deflashing chamber with the majority of media stream being concentrated at a particular area designated in the art as a "hot spot".
• a hot spot prohibits the uniform deflashing of single or multiple parts within the chamber, as well as causing inconsistent wear on the internal components of the deflashing apparatus.
• the prior art deflashing apparatus has typically been fraught with serious transport problems of the media from a storage reservoir or hopper to the throwing wheel. These transport problems have resulted in inconsistent quantities of media being supplied to the throwing wheel and, in. extreme cases, a complete discontinuance of media flow due to clogging within the transport system.
• transport deficiencies With specific reference to cryogenic deflashing apparatus, such transport deficiencies become acute since discontinuance of the media pattern requires the parts to be removed from the cryogenic blasting chamber to prevent the entire part from becoming brittle in the super cooled environment. Further, such shut-downs of the apparatus significantly deteriorate the overall cost effectiveness of the device, and pose safety hazards to personnel being exposed to the low temperature cryogenic environment.
• the prior art apparatus has typically incorporated a large housing, completely surrounding the cryogenic deflashing chamber which is analogous to large reefers or refrigerators with loading and unloading of articles into the chambers requiring personnel to enter therein.
• Such manual entrance into the deflashing chamber is extremely dangerous, posing significant safety hazards to a personnel who may be subjected to cryogen gas poisoning and extreme cold temperatures.
• the present invention provides a deflashing apparatus and more particularly a cryogenic deflashing apparatus which substantially eliminates the deficiencies of the prior art devices.
• the present invention provides a novel impeller or throwing wheel mechanism wherein a control cage is axially positioned and rotatably mounted within the impeller to control -the intake location of media onto the impeller vanes.
• the angular orientation of this control cage may be varied or oscillated during machine operation to continuously shift the area of media concentration across the deflashing chamber.
• a substantially uniform distribution of media across the deflashing chamber is provided which eliminates inconsistencies in flash removal, as well as concentration of wear on the internal components of the device.
• the present invention augments this uniform distribution feature by an improved transport mechanism which delivers a consistant quantity of pellets to the throwing wheel and eliminates the tendency of the media to clog during transport from the hopper.
• an improved transport mechanism which delivers a consistant quantity of pellets to the throwing wheel and eliminates the tendency of the media to clog during transport from the hopper.
• These particular transport improvements are made possible by a novel static head, helical feed screw, and vacuum assisted transport mechanism.
• the static head may be pre-set to a desired level while the speed of the helical screw and magnitude of vacuum assist may be adjusted during machine operation.
• the density, intensity, and pattern of the media stream may be varied to meet the specific requirements of a particular article to be deflashed.
• the present invention overcomes the size deficiencies of the prior art by providing a rather compact deflashing apparatus which does not utilize a surrounding refrigerator housing and facilitates the utilization of conveyor handling techniques during the processing of articles through the apparatus.
• the present invention eliminates the refrigeration units and special handling equipment heretofore utilized in the prior art.
• the prior art's temperature exposure and icing deficiencies have been substantially eliminated by the present invention's utilization of a sealed gas lock door which prohibits interaction between the cryogen environment and the atmosphere during loading and unloading of articles into the deflashing chamber.
• the present invention facilitates the automatic loading of articles into the deflashing chamber by a conveyor belt which feeds the articles from an entrance enclosure into the cryogenic deflashing chamber without directly or indirectly exposing operating personnel to cryogenic environment.
• the entire apparatus incorporates a plurality of baffles, air locks, and openings that may be all automatically operated.
• Figure 1 is a front elevational view of the deflashing apparatus of the present invention
• Figure 2 is a fragmentary right side view thereof, depicting the vestibule structure of the present invention
• Figure 3 is a left side view of Figure 1 showing the vestibule interlock operating means which have been broken away for illustration;
• FIG 4 is a fragmentary view taken from the unseen side or rear of Figure 1 showing the spent media transfer feed mechanism
• Figure 5 is an elevational view of the spent media transfer feed system of Figure 4 extending from the lower to the top portion of the apparatus to provide a continuous flow of media into the storage hopper;
• Figure 6 is an enlarged cross-sectional view of the transport mechanism and throwing wheel of the present invention.
• Figure 7 illustrates an alternative embodiment of the interlock system of the present invention
• Figure 8 depicts a perspective view of an alternative embodiment of the present invention, depicting'the apparatus with the interlock doors exposed;
• Figure 9 is an enlarged cross-sectional view of the throwing wheel and transport feed mechanism of the present invention taken along the lines 9-9 of Figure 8;
• Figure 9a is an enlarged perspective view of the media transport feed screw, control cage, and control cage oscillation mechanism of the present invention.
• Figure 9b is a schematic representation of the variable media pattern produced by the oscillating control cage of Figure 9 ;
• Figure 10 is a fragmentary view of the throwing wheel of the present invention taken about lines 10-10 ⁇ of Figure 9 ;
• Figure 11 is a cross-sectional view of the deflashing apparatus of the present invention taken about lines 11-11 of Figure 8;
• FIG 12 is a perspective view of the media and contaminant separation means of the present invention interconnected with the entire deflashing apparatus.
• a first embodiment of the cryogenic deflashing apparatus of the present invention is shown, being composed generally of a housing or casing C formed in a substantially • rectangular configuration.
• the housing C is preferably fabricated from stainless steel having a double wall configuration with the voids between the opposing walls being filled with suitable insulation, such as a polyethylene foam material (not shown) .
• suitable insulation such as a polyethylene foam material (not shown) .
• This particular insulated stainless steel construction has been found to withstand wear generated by the high velocity media stream, and further prevent heat transfer from the ⁇ ryogen environment to the atmosphere.
• the front wall of the housing or casing C has a door D supported on hinges 10 which may be securely locked in a closed position by a fastener 11 mounted to the periphery of the casing C.
• a seal 12 (shown in Figure 2) is provided between the opposing flanges 13 and 14 of the front wall 19 and the door D, respectively, to provide an air-tight interface between the interior of the casing C (i.e. , the deflashing chamber) and the door D.
• the door D extends transversely outward from the frontal wall 19 to form a vestibule having an inlet or loading section 15 and an outlet section 16 vertically oriented to one another.
• the inlet and outlet loading sections 15 and 16 are separated by a horizontal wall 17 which extends throughout the width of the door D and projects forwardly from the distal end of the vestibule V to reside within the vertical plane of the front wall 19 of the casing C.
• both of the chambers 15 and 16 communicate with the interior of the casing C (i.e., the deflashing chamber) but are vertically isolated from one another.
• a pair of cover plates 20 and 23 are mounted by way of hinges 21 and 24 to the outer walls of the vestibule V.
• Each of the covers 20 and 23 preferably includes sealing means 25 and 26 (shown in Figure 2) as well as latch members 27 and 28 (shown in Figure 1) to seal and maintain the covers in their closed position.
• the vestibule V forms a relatively air-tight closure'or outer gas lock which effectively prohibits interaction between the loading and the unloading chambers 15 and 16 and the atmosphere.
• a pair of inner closure gates 29 and 33 are provided which are pivotally mounted about horizontal axes 30 and 34, respectively.
• the upper closure gate 29 extends across the opening into the loading chamber 15, and selectively engages a peripheral picture frame-like seal 32 mounted on the distal ends of the upper wall 22 and partition 17 of the door
• the lower closure gate 33 extends across the opening from the unloading chamber 16 to the deflashing chamber, and sealingly engages a barrier wall 36.
• the barrier wall 36 is preferably formed as part of the vestibule V or outer gas lock
• A and extends angularly into both the unloading chambers 16 and deflashing chamber.
• both of these gates 29 and 33 are movable between a closed position (as indicated by the solid lines in Figure 2) and open position (as indicated by the phantom lines in Figure 2) to allow selective communication between the loading and unloading chambers 15 and 16 with the deflashing chamber. Further, it will be recognized that in the closed positions, the gates 29 and 33 effectively isolate the vestibule V from the deflashing chamber and form, in effect, an inner gas lock which prevents the cryogen environment from interacting with the loading and -unloading chambers 15 and 16.
• the loading chamber 15 is additionally provided with a loading bin 37 which is pivotally mounted adjacent one end about a horizontal pivot axis 38.
• the bin 37 is preferably formed having radially-shaped sidewalls and an open upper end adapted to receive parts (not shown) through the access cover 20. With the parts loaded into the bin 37, the bin may be pivoted to a position indicated by the phantom lines in Figure 2 to insert or dump the parts into he deflashing chamber.
• an endless conveyor or belt B extends in a generally L-shaped path through the interior of the deflashing chamber having an upper course adapted to tumble parts within the chamber.
• the belt is formed of spaced stainless steel segments to permit the media to pass therethrough and is supported at both of its sides by a pair of chain members 41 which are rigidly attached thereto. These chain members 41 mate with a pair of
• OMPI OMPI .
• WIPO idler sprockets 48 and 49 on their lower course and additionally extend vertically upward to engage a driving sprocket assembly 43.
• the idler sprockets 48 include a threaded adjustment member 47 which may be manually manipulated to adjust the tension on the chain member 41.
• the upper course of the belt B is guided by a pair of large sprockets 52 (shown in phantom in Figure 2) which are carried by a pair of circular discs 53, each mounted to a common shaft 54 and journaled to the sidewalls of the casing C.
• a pair of large sprockets 52 shown in phantom in Figure 2
• a pair of circular discs 53 each mounted to a common shaft 54 and journaled to the sidewalls of the casing C.
• the sprocket drive 43 is driven by a chain drive 56 which extends between an external sprocket 57 mounted to the drive sprocket 43, and a sprocket 58 mounted to the outward shaft 59 of a gear box 60.
• the gear box 60 may be driven by a conventional motor 61 and a timing belt arrangement 62 which engages the input pulley on the gear box 60.
• the motor 61 may be of a variable speed type or alternatively the gear box 60 can be utilized to establish the speeds with which the belt B is driven.
• the tumbling action of the parts (not shown) within the deflashing chamber may be adjusted to provide the most effective tumbling action for a particular operation.
• the gear box 60 provides for reversible rotation so that upon completion of the deflashing operation, the belt B may travel in the direction opposite the arrow shown in Figure 2, whereby the articles (not shown) disposed upon the belt B may be moved off the belt B through the gate 33 and into the unloading chamber 16 of the vestibule V.
• the deflashing chamber additionally includes means for the admittance of a cryogenic gas or liquid, which as previously mentioned, is utilized to embrittle the flash on the articles placed within the apparatus.
• the means comprise an input fitting 65 and piping 67 and 68 which preferably extend through the upper wall of the casing C to direct the cryogen liquid stored in a reservoir (not shown) downward through the deflashing chamber.
• a metering valve 66 is additionally provided.
• FIG 6 the detailed construction of a first embodiment of the throwing wheel and media transport mechanism of the present invention is shown.
• the mechanism is composed generally of a throwing wheel assembly 70, a helical feed screw 89, and a driving assembly 71, which are all removably mounted to the top wall of the casing C.
• the throwing wheel assembly 70 is aligned with an opening 69 which extends through the top wall of the casing C to form the discharge throat of the apparatus.
• the throwing wheel assembly 70 is composed of the throwing wheel or impeller 93, a housing 82, and a skirt or shroud which extends downwardly into the discharge throat 69.
• the wheel 93 is formed having a pair of opposed circular plates 94 with a plurality of • ⁇ symmetrically spaced fins or vanes 96 extending radially therebetween, forming plural radial slots 95.
• the plates 94 and vanes 96 are preferably maintained in position by fasteners 97 extending through the vanes, and interconnecting the plates 94.
• the throwing wheel 93 is axially mounted to the main drive shaft 76 of the drive assembly 71 by way of a drive section 87 and coupling 85 which are respectively attached to the wheel 93 by a plurality
• the shaft 76 is supported by a bearing 77 and is journaled at its distal end 73.
• a pulley 78 is mounted to the shaft 76 which receives a belt 79, powered by a drive motor
• the speed of the drive motor 80 may either be variable via a conventional motor control (not shown) or alternatively be a pulley adjuster 81 which varies the space and thus the effective diameter of the halves of the pulley 78.
• the throwing wheel 93 may be rotated at variable speed to propel media (not shown) through the discharge throat 69 and into the deflashing chamber.
• a helical feed screw 89 is provided to transfer the media (not shown) axially into the throwing wheel 93.
• the shaft 88 of the feed screw 89 is connected at one end to the drive shaft 76 and is journaled at the other end in a bearing 92 supported by an upstanding bracket 91.
• the feed screw 89 is enclosed within a tubular member 90 which is preferably formed of two aligned sections 90a and 90e.
• the section 90a includes an opening 90b which permits the deflashing media to enter the tube 90 as from a hopper 116 (shown in Figure 5) and is maintained stationary by a flange 90c and fastener 90d secured to the angle bracket 91.
• the tube section 90e additionally includes an opening 9Of and is rotatably mounted for angular movement about the shaft 88 of the helical feed screw 89 by a collar 90g.
• the rotatable tube section 90e forms a control cage for the intake of media to the throwing wheel 93 which may be adjusted during operation either manually or automatically to vary the pattern of media discharged from the throwing wheel 93.
• media is supplied from the hopper 116 through the opening 90b in the tube section 90a to fill the area surrounding the helical feed screw 89.
• the feed screw 89 and throwing wheel 93 are rotated by the drive shaft 76 such that the media (not shown) is transported by the feed screw 89 laterally toward the throwing wheel 93.
• An internal impeller section 99 rigidly attached to one end of the shaft 88 of the helical screw 89 causes the media to travel upward into the throwing wheel 93, wherein, due to the rotation of the throwing wheel 93, the media is accelerated across the surface of the vanes 96 and discharged through the discharge throat 69 to bombard the articles within the deflashing chamber. Subsequent to the impact of the media upon the part, it is desirable to recirculate the spent media back into the helical feed screw 89 and throwing wheel 93 assembly.
• the lower portion of the deflashing chamber includes a V-shaped hopper or trough 100 formed by a pair of walls 101 that extend angularly downward from the sides of the casing C.
• the trough 100 is provided with a transfer screw 103 adjacent its apex which is mounted on a shaft 104 supported by bearings 105.
• the screw 103 extends through the rear wall of the case C to communicate with an insulated container 106.
• a -motor or other means 107 may be utilized to rotate the shaft 104, causing the media accumulating in the trough 100 to be transported into the container 106.
• T e container 106 is preferably provided with a screen 108 sized to separate or filter the media from the flash particles freed during the deflashing process, and is positioned in an overlying relationship with the inlet 111 of a screw conveyor, designated generally by the numeral 110.
• the screw conveyor 110 is composed of an outer flexible tube 113 which extends from the container 106 to the hopper 116--positioned above the top wall of the casing C.
• a helical screw 112 having a flexible shaft 114 is disposed within the tube 113 and is connected to a motor 115.
• the helical screw 112 transports the media entering through the opening 111 through the tube 113 and discharges the media into the hopper 116 for entry into the transport and throwing wheel mechanism 93.
• a top closure 106a is provided upon the container 106.
• the particles or parts to be deflashed are placed within a loading bing 37 of the vestibule V by opening the cover plate 20.
• both of the inner gates 29 and 33 of the vestibule V are in their closed position to prevent the transfer or interaction of the cryogenic gas contained within the deflashing chamber with the atmosphere.
• the cover 20 is closed, sealing off the atmosphere from the vestibule V and the inner gate 29 may be released (as by removing a pin 120 shown in Figure 3, or releasing a holding means such as a crank arm 121) to move to the phantom line position, shown in Figure 2.
• the bin 37 containing the articles to be deflashed (not shown) may be pivoted about its axis 38 to a position indicated by the phantom lines in Figure 2, wherein the articles are dumped onto the conveyor belt B.
• the bin 37 and gate 29 may be returned to their initial position, thereby again sealing the vestibule V from the deflashing chamber.
• the conveyor belt B traveling in a direction indicated by the arrows in Figure 2 tumbles the articles on its upper concave course with any articles accidentally moving out of the concavity being urged back thereon by the angularly inclined walls 29a and 29b of the upper gate 29.
• the flash of the articles will become embrittled in comparison with the remainder or main body of the articles so that the media being discharged through the deflashing chamber by the throwing wheel 93 effectively removes the flash from the articles without marring the remainder of the articles.
• the lower gate 33 of the vestibule V may be opened to the phantom line position of Figure 2 (as by the crank 123) and the belt B may be reversed so that the articles carried by the belt B are transported into the unloading chamber 16. Subsequently, the gate 33 may be returned to its initial position to prevent the escape of the cryogen gas, and the lower closure panel 23 may be manually opened to remove the articles from the apparatus.
• FIG 7 a modified vestibule or gas lock arrangement is illustrated which may be substituted for the vestibule V of Figures 1 through 6.
• the loading bin 237 includes a marginal extension or flange 225 adjacent one edge thereof which engages a sealing member 232 formed on the interior surface of the door D.
• a lower seal 232a is mounted on one surface of the partition 17 which in combination with the seal 232 forms a substantially gas-tight seal between the loading chamber 15 and the deflashing chamber.
• the modifi «cation- further provides a baffle depending downwardly from the top surface of the case C to deflect articles being tumbled during the deflashing operation back onto the concave upper course of the belt B.
• the baffle is preferably pivotally connected intermediate its length such that during pivoting of the bin 237 to enter parts into the deflashing chamber (in a manner previously described) , the baffle may extend to a non-restrictive position indicated by the phantom lines in Figure 7.
• the modified vestibule structure includes a lower gate 233 which is pivotally mounted about an axis 234 for movement between an opened and closed position indicated by the full and phantom lines respectively in Figure 7. As shown in its closed position, the gate 233 mates with a top and side seal 235 and 235a to prohibit interaction and heat transfer between the cryogen gas and the atmosphere. Further, the gate 233 serves to redirect any articles back onto the belt B which accidentally are thrown off the belt during the deflashing process.
• the apparatus generally comprises a casing 300, having inner and outer spaced
• the apparatus shown is similar to the prior embodiment, and further comprises a modified gas lock or vestibule 308, an automatic part conveyor 312, a belt tensioning means 370a, flash/media separator 454, and a modified media transport and throwing wheel as.sembly 510.
• the casing 300 is provided with a door 306 which preferably extends across the entire front surface of the apparatus.
• the door 306 includes an outer lock or vestibule 308 which forms a substantially gas-tight loading and unloading chamber 310 and 400, respectively (shown in Figure 11) .
• Manual access to the chamber 300 is facilitated by an outer hatch 330 which is pivoted to the top surface of the vestibule 308 by a hinge 332, whereas access to the chamber 400 is similarly provided by a pair of pivoted hatches 404.
• the chambers 310 and 400 are separated from one another by an automatic part conveyor 312 and are selectively isolated from the deflashing chamber 322 by a pair of gates 324 and 390.
• the conveyor 312 is provided with a series of flights 314 extending along its periphery WM ⁇ G ⁇ -grip and carry the parts along the. conveyor 312. " As shown, the conveyor 312 is driven in the direction of the arrow 318 whereby the parts carried thereon may be automatically deposited onto the tumbling belt 320 within the deflashing chamber 322.. AS will be recognized during this transfer of the parts from the conveyor 312 onto the belt 320, the inner gate 324, which in its closed position extends from the upper portion of the chamber 310 to slightly below the upper-most pulley 422 of the conveyor 312, pivots in the direction of the arrow 326 to reside in a position indicated by the phantom lines in Figure 11.
• the gate 324 forms an inner gas lock which permits limited interaction of the cryogen environment in the deflashing chamber 322 with the atmospheric environment of the loading chamber 310 only during loading of articles into the deflashing chamber.
• the unloading chamber 400 is additionally provided with an inner gate 390 formed having an upper and lower section 392 and 394, respectively, which is pivotally mounted about an axis 396.
• the gate 390 has a closed position (indicated by the full line in Figure 11) , wherein gate 390 sealingly engages the lower wall of the chamber 400 to isolate the unloading chamber 400 from the deflashing chamber and an open position wherein the gate 390 pivots in the direction of the arrow 398 to reside in a position indicated by the phantom lines in Figure 11.
• the belt 320 may be driven in a reverse direction to dump the parts carried thereon into the unloading chamber 400 in the manner previously described.
• the deflashing chamber 322 includes a plurality of axles 350, 352, and 354 which support the belt 320 on sprockets respectively numbered 356, 358, and 360. These sprockets allow the belt 320 to travel in a substantially L-shaped configuration whereby the parts (not shown) may be tumbled in the concave pocket formed upon the upper course of the belt 320 by the pair of discs 342. in this embodiment, however, the belt 320 is tensioned by means of a roller 364 which is mounted about an axis 366 to a support arm 368.
• the arm 368 is a roller 364 which is mounted about an axis 366 to a support arm 368.
• OMP is formed in a dog-leg configuration with the upper portion being connected to a rod 370 that is in turn mounted to a spring 373 and cylinder 374 arrangement.
• the spring 372 biases the rod 370 to provide continuous tension on the belt 320.
• the belt 320 when the belt 320 either expands or contracts in response to the introduction or elimination of cryogen gas within the deflashing chamber 320, the belt achieves a degree of automatic tensioning due to the biasing force of the spring 372.
• the substantial thermal contraction of the belt during operation which often caused premature failure of the belt 320 in the prior art, has been compensated for in the present invention.
• a deflector 378 is additionally provided, being positioned at the interface between the vestibule 308 and the deflashing chamber 322.
• the deflector 378 preferably comprises an upper portion 380 and a lower portion 382 connected at a hinge point 384.
• the upper portion 380 is additionally connected by a hinge 386 for upward pivotal movement in a direction of the arrow 388 to a position indicated by the phantom lines in Figure 11.
• the leg 380 When disposed in its closed position, the leg 380 is angularly inclined toward the belt 320, thereby urging parts accidentally thrown thereon back onto the belt whereas in its open, position, the leg 380 extends outward away from the belt 320, thereby permitting the deflashed articles to be dropped into the unloading chamber 400, without interference from the deflector 380.
• the assembly is mounted to the top surface of the casing 300 in a similar manner to that previously described, with the throwing wheel 510 being aligned with a discharge opening extending into the deflashing chamber 322.
• the helical feed screW 504 and impeller 510 are driven by separate motor drives such that their rotational speed may be independently variable. As will become more apparent below, this independent drive feature permits the apparatus to be finely adjusted to specifically meet the
• the distal end of the tube 521 surrounding the feed screw 504 is provided with a 15 collar 516 having a small opening 520 therein which allows the media to be delivered into the radially oriented spaces 524 formed between the vanes 526 of the throwing wheel or impeller 510.
• this collar 516 may be rotated about its
• the present invention incorporates a control cage 516 which may be rotated during machine operation to continuously vary or oscillate the angular orientation of the opening 520 with respect to the impeller 510. In such a manner, the hot spot may be continuously shifted across the area of the . deflashing chamber 322 thereby promoting • uniform and consistent deflashing operations.
• the collar 5-16 includes a flange 517 adjacent the opposite end from the opening 520. This flange 517 mounts a lever arm 518 extending radially therefrom.
• the lever arm 518 includes an aperture 519 which is sized to receive one end of an actuator rod 523 of a pneumatic or hydraulic cylinder 525 pivotally attached to the casing 300.
• the rod 523 is attached to the lever arm 518 by a pair of fasteners 527 threaded onto the rod 523 and positioned on opposite sides of the handle 518. As is well known, such a fastening arrangement permits the location of the handle 518 to be adjusted along the length of the rod 523.
• the cylinder 525 is energized by selective pressurization and depressurization from a controlled external pneumatic or hydraulic actuator (not shown) to reciprocate the rod 523 thereby causing the collar 516 to rotate (in a direction indicated by the arro in Figure 9a). throughout a predetermined angular rotation consistent with the width of the deflashing chamber 322. By this rotation, the angular orientation of the opening 520 relative the throwing wheel 510 is varied, thereby shifting the area of media concentration across the width of the deflashing chamber 322.
• FIG 9b a schematic representation of the media pattern produced by the apparatus of Figure 9a is depicted.
• the media discharged from the impeller 510 although typically being dispersed throughout the deflashing chamber 322, is concentrated at the localized area indicated by the numeral MA.
• the opening 520 being angularly rotated to the position B, the media is concentrated at the area MB located to the right (as viewed in Figure 9b) from the area MA.
• the concentration of media discharged from the impeller 510 for the positions C and D of the opening 520 are indicated by the numerals MC and MD, which are located to the right of the previous media concentration area.
• the cylinder 525 is continuously pressurized and depressurized to oscillate the opening 520 of the collar 516 throughout the sweep of the positions A through D indicated in Figure 9b.
• the media concentration area or hot spot is continuously shifted throughout the length of the deflashing chamber 322.
• the present invention additionally includes an improved transport mechanism 506 which is independently driven from the throwing wheel 510 to deliver a consistent quantity of pellets to the throwing wheel 510 and eliminate the tendency of the media (not shown) to clog during transport from the hopper.
• a helical feed screw 504 is positioned coaxial with the throwing wheel 510 being connected at one end to a motor by way of a suitable flange .arrangement and terminating at its other end adjacent the opening 520 of the control cage or collar 516.
• the feed screw 504 is enclosed within a tubing member which, as in the previous embodiment, includes a media intake opening adjacent its top surface.
• a media hopper 502 is positioned above the media opening to store a predetermined quantity of media therein.
• the hopper 502 includes a level indicator and valving arrangement (not shown) which regulates the amount of media entered into the hopper 502 to provide a constant static head.
• the feed screw 504 rotates under the power of the separate motor drive causing media (not shown) from the hopper 502 to travel first downwardly into engagement with the feed screw 504, and then transversely towards the collar 516. Due to the constant static head maintained within the hopper 502, the amount of media entering the feed screw 504 will be uniform. Further, during this operation, the throwing wheel 510 being powered by its separate motor drive, is typically rotated at a RPM value substantially higher than rotation of the feed screw 504. This rotation develops a vacuum at the opening or port 520 of the collar 516 which acts through the collar 516 and feed tube surrounding the feed screw 504. As such, the media being transported laterally by the feed screw 504 is vacuum assisted in its travel and urged through a port 520 onto the throwing wheel 510.
• the media is constantly being acted upon during transfer from the hopper 502 to the impeller 510 (i.e., first downward by the force of the static head within the hopper 502, second transversely by the rotation of the feed screw 504, and thirdly transversely and upwardly through the opening 520 by the vacuum generated in the throwing wheel 510) .
• the inconsistent amount of media delivered to the impeller, as well as the clogging problems associated in the prior art, are substantially eliminated.
• this particular transport throwing wheel arrangement permits the apparatus to be finely adjusted for particular deflashing operations. As will be
• the amount of vacuum assist, as well as the velocity of the media from the throwing wheel 510 is related to the speed of the throwing wheel 510, which may be independently controlled and varied during operation. Further, the amount of media being supplied to the wheel
• 10. 510 is dependent upon the speed of the helical feed screw 504, which is additionally independently variable.
• the density, intensity, and the pattern of the media stream may all be varied to suit the particular deflashing operation.
• the hopper includes a transport screw 442 which is driven, as in the prior embodiment, to feed the media into a reservoir container 444.
• the container 444 is in turn connected . to a flexible conveyor means 446 (analogous to the
• the separator apparatus of the present invention basically comprises a plurality of vibratory chambers 454, 456, 458, and 460, each being provided with the respective screen thereunder, which is graduated in size from the upper to lower chambers.
• the media transported through the helical feed tube 452 enters the upper chamber 454 and passes through a respective screen to the lower chambers 456 and 458.
• Each of the lower chambers 456 and 458 are connected as by way of conduits 464 and 462 to the conical-shaped hopper 484. Due to the hopper 484 being maintained under vacuum, the media within the chambers 456 and 458 is rapidly drawn off and transported through the tubes 464 and 462 into the hopper 484.
• the upper-most and lower-most chambers 454 and 460 are connected as by way of conduits 466 and 457 to a flash residue container 470 which is similarly maintained under vacuum.
• a flash residue container 470 which is similarly maintained under vacuum.
• the graduation of screens can be utilized in any suitable manner to allow for the most advantageous separation of the flash and media.
• the order of the chambers and their respective screen size is preferably maintained such that the gauge of opening in the screen decreases from the upper to lower chambers of the separator to eliminate the smallest flash particles at the lower-most chamber while drawing off the media from at least one or two of the chambers thereabove. In such a manner, a suitable separation between the media and flash of the system is accomplished.
• the media falls into a conical-shaped hopper 484 which is supported by legs 480 and 482.
• the hopper 484 is connected to a feed screw and conveyor assembly 490 that is of the helical screw type 446 previously described for conveying the media upwards into the feed hopper 502 of the throwing wheel assembly 510.
• the applicant has found that when the media reaches this hopper 482, its temperature has typically been raised to an intermediate level, i.e., between the cryogenic temperature and the atmospheric temperature, which often attracts moisture and creates a frost condition.
• the hopper 444 is provided with a cal rod 494 which is connected to a power supply as by way of the electrical leads 496 to heat the media to a temperature above the dew point.
• the entire conduit 446 leading to the separator apparatus could be maintained at temperatures approaching the cryogenic temperatures, whereby the formation of ice would be prohibited.
• the separator apparatus of the present invention substantially separates the media from the flash liberated in the deflashing process and prevents a formation of ice on the media being transferred back to the throwing wheel apparatus 510. From the above, it will be recognized that the embodiment of Figures 8 through 12 is particularly suitable for completely automatic operation.
• the opening of the outward hatch 330 of the vestibule structure 308 may be readily accommodated by pneumatic or hydraulic means such as a hydraulic actuator 410 extending therefrom and interconnected to the door by way of a pivot point 414.
• pneumatic or hydrauli cylinder 410 there can be various other means such as a rach and pinion or individual motor drives (not shown) incorporated within the sidewalls 302 and 304 of the casing 300 to drive the inner gates 324, 380 and 392 between open and closed positions.
• a rach and pinion or individual motor drives (not shown) incorporated within the sidewalls 302 and 304 of the casing 300 to drive the inner gates 324, 380 and 392 between open and closed positions.
• the speed of the motors, as well as the operation of the control cage 516 may be controlled by the use of a variety of electrical or electromechanical linkages.
• all the elements of the apparatus can be advantageously automated and connected to a digital control system (now shown) for providing a timed processing of material or articles through the apparatus.
• the system can function entirely under automatic control down to the point of loading and unloading on a conveyor.
• the present invention provides a substantial improvement over the prior art deflashing apparatus.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Processing And Handling Of Plastics And Other Materials For Molding In General (AREA)
• Moulds For Moulding Plastics Or The Like (AREA)

Priority Applications (1)

Applications Claiming Priority (3)

Publications (1)

Family

ID=26724006

Family Applications (1)

Country Status (8)

Cited By (4)

Families Citing this family (6)

Citations (15)

Family Cites Families (5)

• 1979
  • 1979-06-25 WO PCT/US1979/000445 patent/WO1980000140A1/en unknown
  • 1979-06-25 JP JP54501067A patent/JPS6254625B2/ja not_active Expired
  • 1979-06-26 EP EP79301232A patent/EP0006751B1/de not_active Expired
  • 1979-06-26 ES ES481958A patent/ES481958A1/es not_active Expired
  • 1979-06-26 CA CA330,559A patent/CA1112048A/en not_active Expired
  • 1979-06-26 NO NO792145A patent/NO792145L/no unknown
  • 1979-06-26 DE DE7979301232T patent/DE2965313D1/de not_active Expired
• 1980
  • 1980-02-01 EP EP79900765A patent/EP0016088A1/de not_active Withdrawn
  • 1980-02-26 DK DK81180A patent/DK81180A/da not_active Application Discontinuation

Patent Citations (15)

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