Patent Publication Number: US-3874490-A

Title: Pneumatic multi-station remote controlled switching station

Description:
United States Patent 1191 [111 3,8 McAlister Apr. 1, 1975 1 PNEUMATIC MULTl-STATION REMOTE 7l6,087 121190; Nicolay 193%;  
  1,413,505 4 I92 Stump 193 CONTROLLED SWITCHING STATION 3.551.924 I/l971 Schlagel, Jr l93/23 [75] Inventor: Isaac N. McAlister, Sylacauga, Ala.  
 [73] Assignee: The Georgia Marble Company, Atlanta, Ga.  
 [22] Filed: Feb. 20, i974 [21] Appl. No.: 444,025  
 [52] US. Cl. 193/23 [51] Int. Cl. 865g 11/00 [58] Field of Search 222/482; 209/74, 139; 193/23, 29, 31 R, 31 A [56] References Cited UNITED STATES PATENTS 647,749 4/l900 Hell 193/23 /0\ l 52 (8 r 38 .f. 1 2 iii z;  
  I00 l/l Ill ll! so &#39;9 as I! Primary Examiner-Allen N. Knowles Attorney, Agent, or Firm-James W. Grace [5 7 1 ABSTRACT 11 Claims, 3 Drawing Figures Ill Ida-  
 PATENTEU 1 1111111111111 III/III PNEUMATIC MULTl-STATION REMOTE CONTROLLED SWITCHING STATION BACKGROUND OF THE INVENTION l. Field of the Invention This invention is to be used most commonly in the field of transfer of particles of limited range of sizes from an air classifier to a selected receptacle. using air as a means of particle movement.  
 2. Background of the Invention Air classifiers of the type shown in US. Pat. Nos. 3,384,238 and $615,009, now assigned to The Georgia Marble Company, have been found to be very useful in selecting particles within a very limited size range and rejecting particles having sizes above and below the selected range. For example, for certain applications. it has been found that calcium carbonate particles in a size range of between 40 microns and I micron are particularly suitable extender pigments for use in paint, rubber. patties, and latex compounds. The output of the classifier is put into drums. However, it is necessary to insure that only particles of the selected sizes are transferred to the drums or containers for shipment. Since other ranges of sizes can be selected by the same classifier, it becomes necessary to insure that only particles of the selected sizes are put into the containers. As the same apparatus may be used to package particles of different size ranges, it becomes necessary to flush out the tubes. Furthermore, there is a need for an apparatus which will be easily switched from one packaging station to another with a minimum of difficulty. Additionally, since the particles may be dusty, it is well to have a sealed pneumatic system during particle movement.  
 SUMMARY OF THE INVENTION The invention covers a remote controlled switching station for particle movement in which certain output chutes may be selected by rotational movement of se lector plates.  
  It is, therefore, an object of the present invention to provide a novel switching station which can easily transfer airborne particles from a source to a selected one of several output chutes.  
  lt is another object of the present invention to provide a novel switching station in which an input chute can be changed to any one of several output chutes with a minimum of friction and wear on sealing members.  
  It is yet another object of the invention to provide a novel switching station which is fluid tight during particle movement.  
  Other objects and advantages of the present invention will become apparent from the following discussion taken in conjunction with the accompanying draw ings in which like numerals indicate like elements and in which:  
  FIG. I is a cross-sectional view of the remoted controlled switching station of the present invention, except for certain parts which will be added in subsequent figures.  
  FIG. 2 is a top view of a portion of the remote controlled switching station of the invention taken along line 2-2 of FIG. I with certain operating features added. and  
  FIG. 3 is a top view of a portion of the remote controlled switching station of the invention taken along line 3-3 of FIG. 1.  
 Referring now to FIG. I, there is shown in crosss section a portion of the novel switching station of the invention having an upper input section, generally indicated at I2, a control section, generally indicated as [3. and an output section generally indicated as I4.  
  Input section 12 acts to receive particulate matter from a source (not shown) which may be an air separator or classifier, as hereinbefore discussed. The upper portion of input section 12 comprises an input chute I5 which may be a sheet metal cylinder or 4 inches standard cast iron pipe. The lower end of chute I5 is enl5 cased in a steel packing gland stuffing box I7 which forms an air-tight seal between the lower end of chute I5 and the upper end of a sinuous shaped tube or pipe 19. The packing gland stuffing box I7 is welded to the lower end of chute 15, as at 21 to prevent movement or rotation of chute IS with respect to the rest of the apparatus. To complete the sealing arrangement. a steel packing gland 23 in the form of a collar 25 with a peripheral outwardly extending flange 26 has its collar 25 received within a recessed lower portion 27 of stuffing box I7. Packing gland rings 28 of square braided packing material are inserted in recess 27 and compressed by collar 25. Bolts 30 connect collar 25 and stuffing box 17 to compress packing rings 28.  
  To support upper section I0, a series of four steel flat bars 33 (only 2 of which are shown) are welded to stuffing box I7 and to a support ring 35. Support ring 35 is rigidly secured by angle plates 38 to steel plates 40. Plates 40 are welded to the underside ofan outside flange 43. The entire upper section 10 of the multistation remote controlled switching station is thus rigidly held in place and supported on a base (not shown) by steel support beams (not shown) connected vertically to steel plates 40 and to a base or foundation (not shown).  
  Rotatable pipe or chute I9 has its upper end spaced at short distance (about threeeights inch) from the lower end of input chute I5 within the confines of packing gland box 17. The upper end 45 of chute 19 is cylindrical with its rotational axis along the central vertical axis of the switching station. The lower end 48 of chute I9 is displaced from the centcrline by virtue of the sinuous turns ofchutc I9 and is welded to the upper surface of a circular plate 50. A brace rod or bracket 49 for rigidity and support of tube I9 is welded to tube 19 at its upper end and to plate 50 at its lower end. Plate 50 has a circular aperture 52 aligned with the opening in lower end 48 of chute I9. The outer rim of plate 50 has a series of teeth 55 protruding outwardly around its periphery to form a sprocket which can be rotated by a chain, as will be described hereinafter. The center of plate 50 has an opening 56 which is internally threaded to be attached to a threaded protruding reduced end of a rotatable steel center shaft 58. A hex nut 59 is screwed on the protruding threaded end of center shaft 58 to secure plate 50 thereto.  
  The underside of plate 50 has a circular groove 60 which surrounds aperture 52 to receive an O-ring 62. O-ring 62 may be of rubber or other elastomerie material and is slightly thicker than the depth of groove 60 so that it will provide an air-tight seal around aperture 52 where pressed against a plate 65 lying in registration below plate 50. Plate 65 is similar to plate 50 in that it has a circular aperture 66 which can be placed in registration with aperture 52 of plate 50 when suitably rotated into position. For reasons to be discussed later, plate 65 also has four grooves 68 cut into its lower face and spaced symmetrically with respect to the centerline of plate 65. Thus, the grooves 68 are on lines placed at right angles to each other. One of the grooves 68 surrounds apcrture 66. The grooves 68 have a diameter slightly greater than that of aperture 66. O-rings 70 are inserted into grooves 68 and are of such thickness as to extend slightly outwardly of their respective grooves. The outer peripheral rim of plate 65 has a series of teeth 72 protruding outwardly therefrom in spaced relationship to form a sprocket which can be rotated by a chain. The center of plate 65 has an opening 74 which is larger than aperture 56 of plate 50. Plate 65 near the inner edge of opening 74 is secured to an intermediate hollow tubular shaft 80. Hollow shaft 80 is tubular and surrounds center shaft 58 so that center shaft 58 and intermediate shaft 80 can rotate independently of each other, a pair of annular bronze bushings 90 and 91 are.  
 placed between shafts 58 and 80 at each end of shaft 80. Shaft 80 has annular recesses along short portions of each of its ends to receive bushings 90 and 91.  
 An outside tubular shaft I is welded at its upper edge to the inner lower face of plate 43. Tubular shaft 100 surrounds intermediate shaft 80 along most of the length of shaft 80 but is separated therefrom by annular bronze bushings 102. Thus, while tubular shaft I00 is fixed against rotation, intermediate hollow shaft 80 is free to rotate and permits rotation of plate 65 to which it is fixed.  
  To permit lubrication of the shafts to avoid frictional binding, a zerk fitting IIO is attached to the upper end of central shaft 58 which has a drilled center bore and cross-drilled passageway III. Since the diameter of center shaft 58 is slightly less than that of intermediate tubular shaft 80, lubricating fluid can flow between the two shafts. In like manner. a zerk fitting I is tapped into the side of outside tubular shaft I00 to feed lubricant into the area between shaft I00 and the outside surface of intermediate shaft 80. Suitable grease seals are located at each end of bushings 90., 9] and 102 in a well-known manner.  
  Referring now to plate 43, which, as previously explained, is secured by welding to plates 40 and thence to the frame supporting the upper section I0 of the switching station, plate 43 forms the upper fixed terminal for lower section 14 ofthe station. Plate 43 is circular and approximately the same diameter as plates 50 and 65. Plate 43 has four apertures 120 spaced at 90 intervals from each other and at locations such that aperture 52 of plate 50 and aperture 66 of plate 65 can all be brought into alignment with each other and with one ofthe apertures I of plate 43. Each aperture I20 of plate 43 forms the opening for the upper end of an output chute 125. There are four output chutes 125, one corresponding to each aperture I20 of plate 43. Chutes 125 may be pipes or tubes of 4 inches diameter, and are secured in air-tight fashion by welding to the underside of plate 43 surrounding aperture I20. As can be seen for convenience, chutes I are also sinuous in shape and extend away from the ccnterline of the station. lfdesired. bins or sacks I30, capable of receiving the particulate output of the switching station. may be placed at the open extremities of chutes I25.  
  It will be recalled that plates 50 and 65 are rotatable relative to each other and to the fixed plate 43. It should be realized that mere rotation of the plates 50 and 65 not only would destroy O-rings 62 and by frictional rotation, but also could result in severely damaging the Orings as they move across the sharp edges of the openings 52 and 66. In addition, the 0- rings 62 and 70 could roll out of their respective grooves as they pass over the openings 52 and 66 and cause binding of the apparatus.  
  To avoid these problems provision is made for axially moving shafts 58 and 80 which carry plates 50 and 65 respectively. An air operated cylinder I40 is connected to center shaft 58 to move it upwardly and with it, plate 50, out of sealing contact with plate 65. A second air cylinder I45 is connected to intermediate hollow shaft 80 to move it upwardly and with it, plate 65. out of contact with both plate 50 and base plate 43. When both air cylinders are operated, plates 50 and 65 are held out of contact with each other. The reason for the small gap between the upper edge of chute I9 and the lower edge ofchute I5 is now apparent. When plate 50 is moved upwardly, the upper edge of chute I9 is also moved upwardly within the packing box I7.  
 The mechanical connection of air cylinders I40 and.  
 I45 will now be described. Two steel bars I50 and 15] are welded to the underside of plate 43 and extend downwardly in spaced parallel relation to each other to enclose air cylinders 140 and 145. A Ushapcd closure plate I54, having upwardly extending flanges I58, I59. is secured to the lower ends of plates I50 and [51 by bolts I60 and nuts I6I. Air cylinder I45 is secured to plate I54 by a clevis I63 welded to plate I54 and connected to air cylinder I45 at 165.  
  Air cylinder I45 has a central operating plunger I70 which is connected to a bar 17]. Bar I71 is welded to two bars I75 and 176 which extend forwardly inside bars I50 and 15]. Adjustable bolts I and I8] are threaded through bar I71 to provide a means for limiting the amount of forward travel of plunger I70. The leading ends of bolts I80 and I8] strike bar I82 which is fixed by welding or the like to outer bars I50 and I5I. Bar I82 has recesses cut in its upper area to permit free vertical movement of bars I75 and 176. The free ends of bars I75 and 176 have holes 183 and I84 therein to receive bolts I85 and I86 which are secured to the outer surface of intermediate hollow shaft 80. Elongated slots and I9I are cut in steel bars I50 and I5I to permit axial vertical movement of bolts I84 and 185, and axial vertical movement of intermediate hollow shaft 80.  
  Thus. while air cylinder I45 is secured at its remote end by clevis I63 to plate I54. cylinder I45 through its plunger I70 can move intermediate hollow shaft 80 longitudinally vertically forwardly or rearwardly. It will be recalled that intermediate shaft 80 is connected to cylindrical plate 65 so that the latter can be moved forward out of frictional engagement with outside fixed flange 43. In order to provide frictionless clearance for O-rings 70. it has been found that a distance of about one-sixteenth inch for the forward movement of plunger I70 and hence, plate 50 is suitable.  
  In like manner, air cylinder I40 is connected to the inner shaft 58 which in turn is connected to circular plate 50 to move it forward about twice the distance of movement of plate 65 or about one-eighth inch.  
  More specifically. air cylinder I40 is secured to bar I82 by a clevis I95. The operating plunger I97 of cylinder I40 is connected to inner shaft 58 by a U-shaped bracket 200 and bolts 202 and 204 which extend through holes drilled in bracket 200 into threaded holes in inner shaft 58.  
  That portion of the apparatus of the invention which provides for axial separation of plates 50 and 65 from each other and plate 65 from fixed outside flange 43, and the sealing of the plates when in contact has been described. The apparatus and manner of rotation of the plates 50 and 65 to shift end 48 of tube I9 between input chute l5 and a selected one of output chutes I will now be described with reference to FIGS. 2 and 3.  
  FIG. 2 illustrates a top view of the apparatus taken along line 22 of FIG. I and shows upper circular plate 50 which has spaced teeth 55 mounted on an inner shaft 58. A chain drive 210 connects the outer rim of plate 50 to the sprocket wheel 212 attached for rotational movement to the shaft of a motor 2I5. Motor 215 is secured to support ring by means of a support bracket assembly 220. Aperture 52 can be seen in plate 50. On the underside of plate 50 and surrounding aperture 52 is groove 60 with O-ring 62.  
  Encrgization of motor 215 will cause plate 50 to rotate around its axis and move aperture 52 in a circular path to overlie one of the openings I20 of output chutes I25.  
  In like manner, lower plate 65 has its teeth 67 engaging a chain drive 222 which in turn engages a sprocket wheel 225 connected to the shaft of a motor 230. A bracket assembly 240 secures motor 230 to support ring 35. Energization of motor 230 rotates plate 65 so that its aperture 66 is in registration with aperture 52 of plate 50 and with one the openings 120 of output chutes I25.  
  Eight limit switches in four housings 248. 249. 250, and 25I are spaced at 90 intervals around the interior of support ring 35. These limit switches may be Cutler Hammer No. 103 I6H2372G limit switches with adjustable levers. The purpose of the limit switches is to assure alignment of apertures 52, 66 and I20 to provide an open path from input to output through the pipes 19 and I25 in a manner to be explained later.  
  FIG. 3 shows the outer or bottom plate 43 in greater detail with four apertures I20 leading to four output chutes I25. Angle plates 38 (shown in cross-section) are welded to plates which in turn are welded to the underside of plate 43.  
  The operation of the pneumatic remote controlled switching station of the invention will now be described in conjunction with an electrical actuating system which is not shown in detail to avoid ovcrcomplication of the disclosure. However, it should be understood that the electric motors 2I5 and 230. and limit switches 248-25] are interconnected for related operation. The limit switches perform their function of stopping cner gilation ot&#39; the motor and hence rotation of the plates and 65 so that the apertures 52. 62 and I20 can be aligned for any selected one of the four output chutes I25. Air cylinders I40 and I45 are energized by an electro-pneumatic system (not shown).  
  The various functions can be controlled either by a sequential timing mechanism or by the limit switches which control an electrically activated control system. The sequential timing system can be patterned after one which controls the operation of a washing machine in that a constant speed timing control rod is made to rotate upon closure of a start switch. A threaded cam rides along the threaded rod and closes relay contacts as it proceeds along the rod. Closure of the relay contacts controls the operation of the motors and electro-pneumatic air cylinders in a preset sequence of operation so that the two plates 50 and are moved out of contact with each other for frictionless rotation to move input tube 19 to a preselected output tube I25 and to permit alignment of apertures 52 and 66 of plates 50 and 65 respectively.  
  In order to monitor the operation of the station and to recognize which of the output chutes is connected to the input chute, pilot lights can be installed in the electrical system which will indicate which output chute is in operative connection to the input chute.  
  It will be assumed that the pneumatic muIti-station remote controlled switching station is in the operating condition shown in FIG. I. That is, there is an open path from the input chute or tube I5 through sinuous tube I9, thence, through apertures 52., 66 and 120 of plates 50, 65 and 43, respectively, and through output chute or tube 125 into container 130. If it is desired to shift the flow of particulate matter away from the container I30 on the left-hand side of FIG. I to the container I30 on the right-hand side of FIG. I, the following sequence of operations is used:  
  I. A start button (not shown) is operated to initiate the desired change. Generally, this will be a time-delay switch so that there will be a period of between one and five minutes for the system to purge itself before the switch operation begins.  
  2. In a timed sequence, air cylinders I40 and I45 are operated. Operation of cylinder I45 moves intermediate shaft upwardly to lift circular plate 65 away from its contact with plate 43. As previously discussed, the distance between the two plates is approximately onesixtecnth inch.  
  3. Simultaneously, air cylinder I40 moves inner shaft 58 upwardly a distance of about one-eighth inch so that plate 50 is now free ofcontact with plate 65. Thus. both plates 50 and 65 are free of engagement with each other and with outside base plate 43. Motor 230 is then energized and by its rotation through chain 222 causes plate 65 to rotate around its axis, aligning its aperture 52 with the next available opening in base plate 43. One of the limit switches of the group 248-25] will sense the alignment of aperture 66 and I20 and cause motor 230 to stop.  
  4. Following this, motor 215 will be energized and, through chain 210. will rotate plate 50 about its axis until aperture 52 is in alignment with aperture 66 of plate 65. Again, the appropriate limit switch will sense the proper alignment of the apertures and stop further rotation of motor 2I5.  
  5. Following this, air cylinders I40 and I45 are deenergized so that plates 50 and 65 are again in contact with each other and with base plate 43. Air cylinders I40 and I45 are double acting so that extension and retraction of their operating rods is positive in action.  
  6. Rotation of plate 65 has caused the lower end of chute I9 now to be brought in alignment with the upper end of chute at the right-hand side of FIG. I and with aperture 66 in plate 65.  
  In this way, the switching station now has changed so that there is an open pathway between input chute I5 and output chute I25 at the right-hand side of FIG. I.  
 At this time particulate matter of a different size range from that previously collected will be diverted into the container 130 at the right-hand side of FIG. I. When plates and are in their close position. sealing O- rings 52 and are operative to form a fluid-tight passageway from input to output.  
  It will be recognized that while there are four output chutes 125 shown, that more or less can be included without departing from the scope of the invention.  
  It will be recalled that plate 65 has four sets of grooves 68 with an O-ring 70 in each groove. When plate 65 is held against outside plate 43, the Orings 70 surround each of the upper openings in plate 43 to seal the upper openings in chutes 125.  
  It should also be recognized that while chute 15 has been characterized as an input chute and chutes as output chutes. the operation of the mechanism will he exactly as described if chutes 125 are considered to be input chutes and chute 15 an output chute. In this reversed condition, the essential operation of the station is not affected.  
 in summary. there has been described a pneumatic multi-station remote controlled switch station which permits frictionless selection of output chutes in an automatic manner.  
 I claim:  
  I. A station for connecting an input chute to a selected one of a plurality of output chutes. comprising:  
 an input chute having a discharge end and a plurality of output chutes.  
 a first rotatable plate connected to said input chute. said plate having an aperture in sealed registration with said discharge end of said input chute,  
 means for rotating said first plate,  
 a second rotatable plate lying in concentric relation with said first plate and having an aperture therein adapted to he in sealed registration with said aperture of said first plate.  
 means connected to said second plate for rotating said second plate.  
 a fixed outside flange plate having a plurality ofopenings. each of said openings being the input end of one of said plurality of output Chutes.  
 means connected to said first and second plates for axial movement thereof away from each other and from said outside flange plate to align said apertures of said first and second plate with said opening in said outside flange plate.  
 said last named means adapted to axially move said first and second plates into sealed contact with each other and with said outside flange plate.  
  2. A station for connecting an input chute to a selected one of a plurality of output chutes. as recited in claim I. in which said station has an input section. said input section comprising a fixed input chute and a vertically moveahle input chute and an air-tight seal connecting said fixed input chute and said vertically moveahle input chute whereby said vertically moveahle chute can be displaced relative to said fixed chute while an air-tight seal is maintained.  
  3. A station for connecting an input chute to a selected one of a plurality of output chutes. as recited in claim 1. in which said means for rotating each of said plates comprises outwardly extending teeth equidis tantly spaced around the periphery of each of said plates. a pair of sprocket wheels. a pair of motors. each of said motors encrgizahle to rotate a corresponding one of said sprocket wheels and a pair of endless chains. each of said motors interconnecting a respective one of said plates and said sprocket wheels.  
  4. A station for connecting an input chute to a selected one of a plurality of output chutes. as recited in claim 1. in which said first and second plates have cir cular grooves cut in a lower surface of each plate surrounding said aperture in said plates. and sealing 0- rings inserted into said grooves.  
  S. A station for connecting an input chute to a selected one of a plurality of output chutes. as recited in claim 2. in which said second rotatable plate has additional circular grooves cut into its lower surface and O rings inserted into said grooves.  
  6. A station for connecting an input chute to a selected one of a plurality of output chutes. as recited in claim 5. in which the total number of grooves cut into the underside of said second plate equals the number of chutes of said plurality of output chutes and in which each of said grooves is in sealing registration with a corresponding one of said output chutes.  
  7. A station for connecting an input chute to a selected one of a plurality of output chutes, as recited in claim 1. in which said means connected to said first and second plates for axial movement thereof comprises a,  
 first axially moveahle shaft connected to said first plate. a second axially moveahle shaft connected to said second plate and means for moving said first shaft and said second shaft independently in axial direction.  
  8. A station for connecting an input chute to a selected one of a plurality of output chutes. as recited in claim 7. in which said second shaft is a hollow tube surrounding said first shaft and in which an outer fixed hollow tube is concentric with and surrounds said second shaft.  
  9. A station for connecting an input chute to a selected one of a plurality of output chutes. as recited in claim 7. in which said means for moving said first shaft and second shaft are double-action air-operated cylinders connected to respective ones of said shafts for independent movement of each shaft.  
  10. A station for connecting an input chute to a selected one of a plurality of output chutes as recited in claim 7 in which said first axially moveahle shaft has longitudinal and transverse passageways therethrough and lubrication insertion means connected to said longitudinal passageway.  
  l l. A pneumatic multi-station remote controlled station having an input chute and a plurality of output chutes comprising:  
 An input chute having an input end and an output end. said input end lying in a plane along the central longitudinal axis of said station.  
 a first circular plate, said first plate lying in a plane normal to said central longitudinal axis of said station with its center lying on said central axis so that said first plate revolves around said axis having an aperture thercthrough located away from said central axis.  
 said output end of said input chute being secured in fluid-tight relation to a surface of said first plate in concentric covering relation with respect to said aperture in said first plate.  
 sealing means surrounding said aperture means connected to said first plate for imparting rotational movement thereof LII  10 ings therein, each of said openings being the input end of a respective one of said output chutes. said first and second plates being adapted for rotational movement so that their respective apertures can be aligned with one of said plurality of openings in said outside flange plate, means connected to said first and said second plate for axial movement of said plates, whereby said plates can be moved toward and away from each other and toward and away from said outside flange plate prior to and following said rotational movement of said first and said second plate.