[1]United States Patent Office 3@197@26,1 3,197,261 SYMM FOP. FW-EDING AIND TP-ANSPORTLNG YAATERIAT-S John H. KaL3ffman, Crystal Lake, El., assignor to Herbert Simpson Corporation, Chicago, ]H]., a corporation of 11'3ineis FUed Mar. 9, 1964, Ser. No. 350,162 5 Claims. (Cl. 302-55) The present appjication is a continuation-in-part of the copendin.- application Serial No. 226,339, fded Sept-.mber 26, 1962, and assigned to the same assignee as the present application. This invention relates to a system for feeding and transportinmaterials and is more particularly concerned with a system for feedin.- materials at a metered flow rate and transporting the materials thus metered to various locations. ,@4-n object of the present invention is to provide a new and improved system for feeding and transporting materials which is simple and economical in operation and construction, and one which will readily handle a variety of different materials. Another object of the invention is to provide a new and improved system for feeding and transporting materials in which the materials are fed and transported at a metered rate which is easily adjustable to handle a variety of different materials at a variety of dh'ferent metering rates. Another ooject of the invention is to provide a new and improved system for feeding and transporting materials in which abrasive materials, such as sand, grit and the like, can be handled with a minimum of wear and abrasion on the system. Another object of the invention is to provide a new and improved system for feeding and transportin.- materials in which solid materials are fed at a metered rate into a fluid flow for transportation to various locations. Another object of the invention is to provide a new and improved system for feeding and transporting matp-rials in which solid materials are fed at a metered rate -@vhich is relatively constant and in which the materials being fed are prevented from brid-ing or building up and causing the flow to stop or the rate to change a substantial amount. Another object of the invention is to provide a new and improved system for feeding and transportin.- materials in which solid materials, such as sand, grit, powder and the lik-e, are fed at a metered rate into a pneumatic transport duct having a pressure different from the feed hopper contairiing the materials. Another object of the invention is to provide a nevr and impro,,ed feeder which can be utilized to feed materials into or olit of a pneumatic transport duct from an area of low to relatively high pressure or vice ver-Qa while maintainin-. a relatively constant rate of flow for a variety of materials and a variety of different flow rates. A further object of the present invention is the provision of a new and improved feeder for feeding solid matrial into a pneumatic transport duct which includes reciprocally movable valve means in a valve chamber and a controllable pnelimatic feed means adjacent the discharge end of the chamber for moving the discharged material from the valve chamber into the duct at a controlled rate of flow. A still further object of the present invention is the provision of a new and improved feeder of the type described in the precedin.- paragraph wherein means are provided for moving the valve means and operating the pneumatic feed means in selected synchronous relation with ore another in order to provide a more constant rate of flow of material into the transport duct. l,tented July 27, 1965 2 Yet another object of the present invention is the provision of a new and iinproved feeder for delivering solid materials into a pneumatic transport system wherein there are provided reciprocally movable valve means in a valve chamber and pneumatic nozzle means adjacent the discharge end of the valve chamber for feeding material discharged from the chamber into the system at an even flow rate which is adjustable from very small flow rates in the order .1 lb. per hour through la wide ran.-e to high 10 flow rates in the order of several thousand pounds per hour. The foregoing and other objects of the present invention are accomplished by providing a system for feeding and transporting materials including a flow duct having 15 a fluid flow therethrou.-h. A hopper is provided for containing the materials to be fed and transported, and this hopper is connected to the flow duct through a valve chamber. The chamber is provided with a pair of opposed valve seats and a valve member is reciprocally 20 mounted in the chamber which moves to alternately seat against first one valve seat and then the other. Means are provided to reciprocate the valve means to accomplish this alternate seating to allow the material to flow from the hopper into the chamebr when the valve member is 25 satd a@ainst one seat and then from the chamber into the flow@duct when the valve member is seated against the other seat. According to another embodiment of the invention, the valve chamber is provided with three seats and a valve 30 member is movably mounted therein to alternately seat first against one seat allowing material to flow from thehopper into one portion of the chamber and from another portion of the chamber into the flow duct and then against the other two seats for allowing the material to 35 flow from one portion of the chamber to the other portion thereof. A further embodiment of the invention comprises a valve chamber having four seats which define three subchambers with a valve member movably mounted therein 40 to alternately seat first against two of the seats to allow material to flow from the hopper into the first subehamber and the material in the first subchamber to flow from the second subchamber into the third and then to seat against the other two seats to allow material to flow from 45 the first subehamber into the second and material in the third subchamber to flow into the flow duct. In yet another embodiment, a valve charriber is provided with four seats -vvhich defme three subchambers and contain a pair of individually controlle,4 movably mounted 5o valv, m,mb,,,. One valve member is independently controuable to altemately seat first against a first seat to allow material to RDw into a first subchamber from the hopper and then to seat a,@ainst a second seat to allow material to flow from the first siibchamber into a second 5,5 subehaniber. The other valve member is independently controllable to alternately seat first against the third seat to allow material to flow from the second subchamber into a third subchamber and then to seat against a fourth seat to allow the material to flow from the third subcham60 ber into the flow duct. In still another embodiment of the invention there is provided a feed hopper for solid material with a discharge outlet at the bottom thereof and a valve chamber of the type described disposed at the outlet of the hopper. 65 Within the valve chamber is provided a reciprocally movable valve member having upper and lower valve el,.-ments which are movable to seat altemately against upper, and lower seating surfaces in the chamber. Below the discharge end of the chamber there is provided an 70 elbow fitting, the outlet of which is connected to the transport system. Slidably positioned within the fitting and coaxially. aligned with the outlet thereof, there is
[2]3 provid-.d pneumatic nozzle means for directing a high velocity air stream into the material as it is dischar-,Cd from the valve chamber to feed the material into the transport system at an even flow rate. Means are provided for actuatin6 the reciprocal valve member ;@nd i@ontrolling air flow to the nozzle means in a selected synchronous relationship with one another to provide for aTi even flow of material into the system at a desired flow rate which may be selected from a broad range in order to handle a variety of materials at a variety of different rates. The speed of reciprocation as well as the time duration. that the valve member is seated on e;ther seat of the feeder rfiechanisms described above can be easily aid automatically controlled and adjusted to re@.Ulate the flow of a variety of different materials under a variety of different operating con,,Iitions. Other objects and advantages bf the present invention will become apparent irom the folloiving detailed description when taken in conjunction with the @drawings in which: FIG. I is a sect;onal, clevational view of a material feeding and transporting device as charactei-ized by the features of the present i-nvention with the sectional portions takeii substantially along line 1-1 of FIG 2; FIG 2 is a secional view taken. substantially along line 2-1@ of FIG. 1; FIG 3 is a schematic diagram of one embodiment of a mechanism for reciprocating the valve disks of the material feeder of FIG. 1; FIG 4 is a schcmatic diagram of another embodiment of a mechanism for reciprocating the valve disks of the n,aterialfeede rofthepresentinvention; - FIG 5 is a sectional, elevational view of another embbdiment of the ptesent invention -,vith the sectional portions taken substantially alon-, line 5-5 of FIG. 6; FIG. 6 is a sectional Niiew taken substantially along line 6-6 of FIG. 5- 1 FIG ' 7 is a sectional, elevational view of another embodiment of the-present invention utilizi,n.- a -triple valve means; @ FIG. 8 is a sectional, elevational view of yet a-tiother embodiment of the present invention utilizing a quadruple valve means@ FIG. 9 is sectional, elevatio,.ial view of still another en-ibbdiment of the present invention utilizing two indep.-.,idently controll,-d valve menibers; FIG. 10 is a sectional, elevational view of a feeding cliamber similar to the one shown in FIGS. I and 2 but utilizing a modified valve mechanism; . FIG. 11 is a sectional, elevational vieu, @of yet another 6nibodiment of a material feeding and transporting de-vice characterized by the features of the present invention; and FIG. 12 is a sectional, elevational view of yet anotherembodiment of a material feeding device of the present invention which includes pneumatic nozzle mcaiis for effecting a more even flow rate of material into the transport duct. Portions of FIG. 12 are shown in schematic form to more clearly illustrate the means for actuating the device. Rei'err-@'ng now to the drawin.-s and particularly FIGS. I and 2, ther-e is illustrated one form of a material feeding and transporting system as characterized by the features of the present invention and indicated -en-rally by the reference numeral 20. The material feeding system " includes a hopper 22 for holding a quantity of material 24 which is to be j'ed and transported by the system. The hopper 22 is provided Nvith a sloping botto@ -i-i wall 26, a pair of slopin- side walls 28 and a vertical front wall 30 The walls may be join@d together to form the hopper in a conventional manner such as welding or flange and bolt construction. If greater hopper capacit3r is desired for holding larger quantities -of material, a large hopper 32 can be attached to the top of the hopper 22 iii a conventional manner, such as by Nvelding or bolts and flange construction. Adjacent the center portion of the front wall 30 of the hopper 22, there is provided a generally rectangular feedin.- chamber 34. The feeding chamber 34 is formed by the Lront wall 30 of the hopper 22, a pair of vertical s;de walls 36, a top wall 38, a bottom wall 40 and a front vertical wall 42. The front wall 42 is comprised of an outer expanded metal screen 42a and an inner 10 cotton filter or vent cloth 42b which wiR pass air bit retai@i the material or may be of solid material such as clear p@'astic when the chamber 34 is either pressurized pr evacuated as required in some types of systems. The front edges &f the side walls "-'6, the top wall 38 and the 15 bottom wall 40 are orovided -,vith flanges to which the front wall 42 is boltid by means of the bolts 44 so that the front wall can be easily removed for cleaning out the cliamber when necessary. A gasket 46 is provided betw,,cn the front wall 42 and the flan,@e to effect a 20 material ti.-ht seal therebetween. The front wall 30 is provid.-d with an openin.a or cutot,,t 39a at the bottom central portion thereof so that inatertal in the hot)per 24 - will readily flow into the feedin.- chamber 34 f6r feeding into the system. There is 25 also provided on the front wall 30 a slidable gate 31 which is attached to the - ,@iall 30 by means of slots in the gate an-d bolts and wing nuts 31a.so that this gate may be adjusted as d.-sired to vary the size of the opening as requircd for diferent systems. The bottom wall 40 1-nay 30 be integrally forn-led with the wall 26 of the hopper 22 or attached tliereto in a conve@itional mann,-,r, such as by welding. The bottom wall 40 of the feeding chamber 34 is provided with. a feed opening 40a through which maerial fiows into a valve chamber 48. 35 There is also provided an internal baffle plate 41 -vvhich prevents the material from flowing directly from the opening in the wall 30 against the front wall 42 and thus al'--ows air from the valve chamber 48 to flow freely up through the opening 40a in the bottom on the outer 40 side of the, baffle plate 41 to escape out the front wall 42 if so desired. The valve chamber 48 is attached to the bottom wall 40 iii coaxial relation to the opening 40a thereof by means of roll.ed angle ring 51 and a plurality of bolts 51a. A -asket 53 is positio.7ted between the horizontal flange of 45 t'@le angle rin,@ 51 and the bottom wall 40 to provide a scalt therebet@,veen and to isolate the hopper and feeding chamber Lro.-n some of the vibrations pres.-nt in the valve chamber when the sysein is in operation. The valv@- chamber 48 is substantially cylindrical in its 50 mid por-tion and is provided with inwardly converging walls at its upper end which provide a generally conical seating surlac-- 4,Ra and terminate to form a feed openiii.48b which is of smaller diameter than the cylindrical portion adjacent the middle of the chamber. The lower end 55 of the chamber 48. is also provided with inwardly convergiiig walls ivh;cb, provide a -enerally conical lower se-,iting surf,-,ce 50a and terminate to form a lower discharge opening 50b which is smaller in diameter than ii'ie mid cyl.;ndrical portIon of the chamber. 60 - For ease in constrtiction and to faci'litate the cleaning of the charr@ber 48, it is constructed of aii upper m.-mber 52 a@id a lov,,er memb.-r 54 whi-,h are provided with flanges and are held to,,ether by a plurality of bolts 56. A @asl@:et 58 is pro-- ,,id@-d betwe--n the flanges of the mem65 bers 52 and 54 to provide a seal therebetween. Th-- upp.-r member 52 is joined to the vertical flange of the angle rin@@ 50 by welding or other suitable means. The lower end of th e valve chamber 43 is attached to a flow duct 56 so that material may be fed from the chamber into 70 th-- duct I through the opening 50b. Depending ii_t)on the relativ.- diameters of the opening 50b aiid the duct 56, an opening 4of the proper size is cut into the dlct and boltorn plates 53 are provided gG that an airti.-.%t co.-inection between the inside of,the chairber 4b' and t,he inside of tho 75 dlct 5@5 is obtained.
[3]5 Within the chamber 49 there are provided a pair of coa,-,ial, parallel aligned upper and lower valve disks 60 and 62. The valv-- dis&s are positioned on an axially ali.-ned threaded rod 64 so as to move together as a unit. 'fhe disks are constructed of resilient material such as hard rubber and are secured ir@ Dosit--'oji on the rod relative to each other by means @of was@ers,a@nd nuts on each side of the disks. l@Piaen the rod 64 is in its upper position as shown in FIG. 2, the upper disk 60 is seated against the surface 48aDf the valve chamb@-r and the lower disk 62 is spaced upwardly ftom the lower seating surface 50a of the chamber. In this position, the chamber 48 is sealed off from the feeding chamber 34 but is open to the duct 56. When the rod 64 is in the lower position as shown in FIG. 1, the upper disk 60 is below the seating surface 48a of the chamber and the lower disk 62 is seated a.-ainst,the lower seating surface 50a of the chamber. In this position the chamber 43 is open to the feeding chamber 34 and is c'losed to the duct 56. The spacing of the valve disks 60 and 62 from each other can easil37 be changed from time to tl-ie to conipensate for wear on the disks and seating surl'aces and to adjust the travel distance of the rod necessary to alternately seat the disks by looseniig the nuts holding the disks on the rod. Similarly, the disks can also b@- rotated to compensate for uneven wear on their peripheries. When the disks are in the pos@'.tion shown in FIG. 1, n. aterial flows into the chamber 48 from the feeding compartment 34 but cannot flow from the chamber 43 into the duct 56. The rate of flow is dependent upon a variety of factors including the floivability of the material itself, the size of the oi)en;ng 43b, the density and particle size of the material, the di'Terence 'm pressure betvieen the chamber 43 and feedina compartment 34, the distance the valve disk 60 is moved from it3 seated relation and the time interval that the disk is open. Whe-ii the disk-s are iTi the posit;on shonvii in FIG. 2, the material in the feeding compartment 34 cannot 4low ir@to the chamber 48 but the material accun-.ulated -ir., the chamber 43 flows o-Lit the opening 50b into the duct 56 and is transported in the duct to the desired location. The rate of the flow is dependent Lpon a variety ol' factors including the aniount of material in the chamber ivhen the disk 62 is open, the flowability of fne rnaterial itself, the size of the opening 50b, the size of the duct 56, the pressure differential between the chamber 1,8 and duct 56, the distance th.- valve disk 62 is mo-ved from its seated relatibn and the time interval that the disk is o-pen. T@f it is desired to reduce &ie rate of flow of a gi-%ren size mechanism, a cylindrical wall 61 can be inserted between the upper and lower valve disl@-s 60 and 62 as is shown in FIG. 10 of the drawin,-. The cylinder 61 decreases the effective volume oll the chamber 48 and prevents a build-up o'L material between the valve disks whicii mi,- ht otherv,,ise occur. One of the most imoortant factors in the feed rate of the mechanism is the amount of time intervals in which the disks are in the up and down position. It has been found by experiment that a large difference in feed rates for a -iven size chamber Pnd given material can be obtained by varving th.- time intervals in the up and down positions. It'has also been found that better flow is obtained by utilizin.- a hi,@h speed of valve movement limited, of course, so that inertia forces do not become great enou-h to be destructive to the mechanism. The feed mechanism can be utiezed to feed materials into the duct 56 when the pressure in the duct is both below and above th-- pressure in the hopper 22 with good results. If the pressure in the duct 56 is greater than in the hopper 22, a small arnoiint of air will flow upward into the hopper during the up or down movement of th-- disks. However, the amount is small because of the rapid speed of inovement of the disks and the compaction of the material over or under the disks betwe.-n the seat forming a temporary seal. Ho,@vever, the majority of this air flow 3,197,261 6 will take place at the path of least resistance which is to the left of the baffle 41 as viewed in FIG. 2 since there is little or no accumulation of material at this point because of the action of the baffle. This air then passes out through the front wall vent cloth 42b and the expanded metal screen 42a to the atmosphere. Some of the vibrations of the mechanism are transmitted to the hopper 22 and feeding compartment 34 and this aids the material to flow freely as well as prevcnts bridging and build-up 10 of materials. When the pressure in the duct 56 is I-,ss than in the hopper 22, the small amount of air flow into the duct similarly aids the material to flow. The utilization of resilient valve disks altemately seating on generally conical seating surfaces provides a high1,5 ly successful feeding mechanism that will handle even the grittiest and most abrasive material with a minimum of wear @on the mechanism. Furthermore, it has been found that a vibratory feeder of this type can operate at much higher feed rates than other types of feeder mech20 anisms. Furthermore, a larger range of feed rates for a variety of different niaterials can be readily obtained by varying the time intervals that the disks are in the up and down positions. It is to be noted that the time in the uo or ii 25 the down position does not necessarily have to be equal. For normal operations the period of dwell in the up and down positions can be :approximately equal. As an exarnple, it was found that in feeding granular bentonite from atmospheric pressure into an air stream of 4 30 the dwell in the down position of 10 secs, and in the up poist of 2 secs. produced a high feed rate and that by extending the time interval in the down position the feed rate is decreased. Some meterials feed best with a slow cycle while others work best at a rapid cycle. Valve @-, 5 movement average velocities in the range of 40 to 100 f-P.m. have beeii utilized to good advantage. Also the novel construction of the mechanism is practically selfcleaning and requires very little maintenance because of the vibration and the use Df flexible disks alternately 40 @eating on slibstantially conical seats. For ease in moving the feedin.a mechanism from one p'@ace to another, -a pair of rollers 57 shown in dotted lines in FIG. 2 may be provided. In order to provide Lor the up and down reciprocation of the rod 64 and the valve disks, the upper end of the 45 rod 64 is connected to a piston rod 66a of an air cylinder 66 by means of the flexible coupling 68. The coupling 68 allows the lower end of the rod 64 to be laterally flexible enough to -provide good seat.;ng of the disks 60 and 62 and also serves to reduce the shock of th@- cylinder 66 when the valve disks seat. The cylinder 66 is mounted on the top wall 38 in axial alinm-@nt with the opening 40a in the bot-tom wall and the valve chamber 48. One system of actuating the cylinder 66 to produce 55 controlled movement of the rod 64 and alternate seating of the disks 60 and 62 is illustrated schematically in FIG. 3. This system is op@,rated by compressed air and requires no electrical power and, hence, is useful in a van'ety O.'L field locations where power is norl readily available. 60 is Compressed air from an air compressor or other sour-le connected to the inlet line 70 at the arrow A. The line 70 is provided with a regulator and pressure reducer valve 72 to regulate the pressure to the system and control the speed of movement of the piston in the cylinder 66. The 65 inlet line 'IO is connected to the inlet port 74a of a sliding type 4--way reversing valve 74. The valve 74 is provided with a sliding valve member 76 having a plurality of different passages for directing the air flow to reverse the @direction of movement of the piston rod 66a in the cylin70 der. -Wh--n t@he valve member 76 is positioned as shown in FIG. 1, compressed air from the inlet port 74a is ditected to the upside end of the cylinder 66 through the line 78 causing the piston rod 66a to move rapidly upward, the 75 speed of movement depending on the setting of the regu-
[4]7 lator valve 72. Air in the downside of the cylinder 66 is forced out through the line 30, a passage in the valve member 76, and out the exhaust port 74b to the atmosphcre. DLiring this time, hi.-h pr,-ssure air from the line 73, is directed to the insid,- of the valve chamber 48 to aid in flushin.- the material out into the duct 56. A check valve 82 is prgvided to prevent back flow of air and mateiial into the system from the chamber 48 and a throttle valve 34 is provided to control the rate of air flow into the chamber 43 and consequently control to a certa@in extent the rat@3 of feedin.- of the material from the chamber 43 into the duct S6. 1-1;1-h pressure air is also directed froni the line 7'a through a throttlin.- valve 36 into a cylinder 83 -havin- a piston and rod 93a connected to one end of the slide leriiber 76 of the valve 7,@,. A check valve 90 is provided in parallel with the valve 86 so that air flow from the line 73 to the cylinder 88 can be controlled by regulation of the tlirottle val@i-- 86. A cylinder 92 and piston and rod 92a are also provided at the other end of the valve 74 with the rod 92a being con-iiected to the other end of the slidin.- valv-. member 76. The cylinder 92 is r-onnected to the line 80 through a check valve 94 and thro@tlinvalve 96. When the valve member 76 is posi-tioned as shown in FIG. 3, air in the cylinder 92 can CXhaust throu,-h both the check valve 94 and throttlin.@ valve 96, the line $0, and out through a passage in the valve inemb-.r 76 and exhaust port 74b. The val@,,e 74 is of the type commonly referred to as the stick-slip type which reouires a areater force to iniii-.Ily move the slidin,- meniber 76 than it reqliires to keep the member moving after it has started mov,ng. Co@isequ--ntly, with the member 76 in the position shown in FIG. 3, the pressure in the cylinder 88 gradually builds up at a rate controlled by the settina of the throttle valve 86 until the pressure difference betwee@i the cylinder 88 @and the cylinder 92 is sufficient to cause the valve member 76 to slide rapidly downwardly to reverse the dire of air flow to the cylinder 66. When this happens, high pressure air is directed to the line 90 causing the piston rod 66a to move rapidly downward and seat the lov,,er valve disk 62. T-he air in the lower cr@d of the cylinder 66 passes through the line 78, through a passa.-e in the valve member 76 and out the exhaust port 74b to the atmosph,-re. The high pressure air in the line 30 is then directed into the cylinder 92 at a rate controlled by the throttlin.- valve 96 and air in th-cylinder 83 is ex@hausted to atmosphere throiigh both the check valve 90 alid throttling valve 86 until the pressure difference between the cylinder 92 and the c@ylinder 88 is sufficient to overcoriie the stickin.- force in the valve 74 o.nd cause the valve member 76 to slide rapidly upward and reverse the pressure flow to the cylinder 66 and start @anot,her cycle of operation. Thus, the control system illustrated in FIG. 3 provid-,s a means for actuating the cylinder 66 in order to move the rod 64 up and donvn and alternately seat the valve disks 60 and 62. The rate of movement of the rod and valve disks is easily ;controlled by the pressure regulator valvp72. The time interval dl,.ring which the rod and va]Nle disks are in the up position is readily controlled by t throttling valve 86 and thp. time interval in which the rod and valve disks are in the down pos@tion is controlled by the throttling valve 96. The throttlin.a valve 84 controls the rate of material flow from the chamber 48 into the duct. . Another system for actuating the cylinder 66 to reciprocate the rod and valve disks is schematically illustrated in FIG. 4 of the,drav@,ing. In this system a solenoid controlled, sprin@ return, 4-way -dr valve 100 is used to revise the air pressure flonv to the cylinder 66. The valve 100 is provided with a sliding valve member 102 @havin@ a plurality of passa,@eways therein aid a retlirn sprin.a 104 Nvhich normally b'iases the member 102 in the down position. Air under pr@-ssure from an air conipressor or other 3,197,-961 source is connected to an i-@ilet line 106 at the arrow A'. The line 106 is connected to an inlet port 100a of the valve 100 and a pressure re.-ulator valve 72' is provided to control the inlet pressi-ire and function similarly to the valve 72 of tiie syst@-m shown in FIG. 3. The high. pr,-ssure air from the inlet port 100a go-,s throi-igh a passa.ce i-@i the slidin- valve member 102 to th-- line 73' which is @connected to the cylinder 66 to raise the rod and valve dl'sks to the up position. High pressure air is also directed 10 :.@'ro--Lli th.- line 73' to the throttle valve 84-' and ch--ck valve 92' v@ihich ftinction in the same manner as described previo,,isly for th,- valves 82 and 84 of FIG. 3 and thence to the chamber 43 to flush it oiit. Air in the upper end of tha cylinder 66 passes through the line Q.0', a passage in 15 the slidiii- valve meriiber 102 and out an exhaust port 100b c)f t'he valve 100. The valve merpber 102 is provided viith a rod 192a of magnetic material. A solenoid coil 106 is connected when eiergized to exert a pull on the valve mer..-iber 102a, pullin.- the slidina valve member 20 102 upward to the position shown ii FIG. 4 against the force of the return spring 104. When the coil 106 is deenergized the sprino. 104 moves th-- men-iber 102 downward so that the inlet port 300a is in communication with the line 80' and the exhaiist port 100b is in commu25 nication with the line 73'. Thus, if an electrical power failure should occur, th.- valve member 102 would move downward u-iider the force of the sprip- 104 direcdng hi.-h pressure air to th,- line 80' and move the rod and valve disks to the down t)osition to shut off any material 30 fiow from the charib--r 43 to duct 50. The coil 106 is energized and deenergized for controlled intervals of time by means of an electri-- power source (not shown) through the onoff switch 110 ' fuse 112, and timer 103. Ref-errin.- now to tle timer 1-08, N@,-7ae@i the feeding de35 vice is to be placed in operation, the maiii switch 1.10 is operated to a closed condition so that a circuit is cornpleted throti.-h la normali'y closed pair of contacts 114 in the timer '@03 to energize the windin.- 106 of the solenoid. This shifts the vali,e as.@ombly 100 to the position 40 shown in FIG. 4 in which compressed air is applied to the lower end of the piston 66 to elevat-. the valv-. disks to the up position. The closure of the switch 110 also completes i circuit throu@_,Ii a pair ol- normilly closed contacts IICA in a switch 116 in the timer 103 to com4 -0 plete an energizing circuit for a forward cirive motor 118 included in the timer 103. When thc@ timer lpotor 118 is energized, cani m--ans cornected ther-.to are driven in a forward direction to initiate tiiat timed interval that the valve assembly 100 is held in its operated condition. 50 After a predetermined period of t'me, the cam means driveii by the motor II,' opeiis the normally closed co-@ltacts li4 and 116a and closes a pair of normally open contacts 116c in the switch 116. The openin.- of the contacts 114 interrupts the en.-r,-izi@-ig circtiit for the 55 winding 106 so t--@at the compression spring 104 restores the valire assembly !LOO to - its al@-ernate condit;on in vhich compress@-d air is supplied to the ,ipper end of the piston 66. This operates the valve disls to their alternate or down pos,'@tion. The openin,- of the contacts 116a 60 terniinates- th.- energization of the forward drive motor 113, and the closure of the contacts 116b energizcs a reverse drive motor 120 that also forms a part of the timer 108. Th--- n-iotor 120 drives the cam means in a reverse directio-i. 65 After a predetermired p-,riod ot time, the cam means now bein.- driven by the r,-vers@- drive motor 120, advances to a position in wbich the contaets 114 and 116a are a.-ain closed a-iid ti-ic cont,,icts I'@r3b are opened. The closed contacts 114 a@ain energize th,- winding 106 to op70 erate the valve assembly 100 to iLs illustrated position. The closing of the contacts I'l@6a e@i--rgizes the motor l@13, and the ope@-iin- of the contacts Ilub @stops tlc motor 120. Thas, th-, tim.- intervals durin.- whicl@i the valve @disks ,ire either ii the uLp position or down position can 75 be controlled by s-.tt@n.- the tinier '%.03 and a variety of
[5]8,197,261 9 desired time intervals can be easily obtained. Th@- operat,'@on of the feeding device is terminated by opening the main switch 110. Thus, the dmer 108 energizes the solenoid coil 106 for an adjustable p-.riod of time causin.@ the valve mem- 5 b.-r 102 to direct period to 'the line 78' to move tn-- rod and valve disks to tbe up position and remain there for the timed -interval. The timer tiie-@i deener.-izes the solenoid and the spring 104 moves the valve meniber to the downward position directing high presslire to the line 10 80' to move the rod and valve to the dc)wn position for a timed interval until the solenoid 106 is again - energized to repeat the cycle. Referrin.- now to FIGS. 5 and 6 of the drawings, there is illustrated another embodim,-nt of the present inveii- 15 tion havin.- a differpnt valve chamber and valve disk arran,@cment. The material hopper and compartment are essentially the sam-- -as shown in the embodiment of FIGS. 1 and 2 and have been -iven @imilar reference nunerals -%vhere the parts are similar or identical. 20 The bottom wall 140 of the feeding compartmept 34 is provided with a somewhat larger feed oper@in.- 14-Ga vihich communicates with the upper end of ;a valve chamber 148. The upper end of the valve chamber 'A48 .'s provided ivith outwardly slopin.a walls formin.- a gen- 25 erally conical upper valve seating surface 148a. The upper end of the walls are terminated in a radial Ran,-e 151 ivhich is attached to ',he bottom wall 140 of the feedin.- compartment 34 by means of the bolts 151a. A gasket l@5e@ is inte-posed between the botto@i-i ivall 140 and 30 tl-lc fiange 151 to p,@ovide a seal therebetwee-.1. The walls formin@ the lower portion (>f t'@ie chamber 148 tap.-r outwardly to form a generally conical lower valve seating surface 150a. The seating surfaces 148 and 150a are joined to-ether by a generally cylindrical -@niddle portion 35 153 which is smaller in diariieter than the valve disks 160 and 164. The lower end of the loiver tapered seatin.- surface 150a forms an outlet openii.a 150b whl:ch communicates with the interior of the duct 56 by means of the cylindrical chamber extension 148c. Th-. - coniplete 40 chamber 148 is formed of an upper memb--r IS2 and a lower member 154. These rjr@embers are joined - to.@ether adjacent tne mid-portion 153 of the chaniber by r@icans of the fiang.- and bol't connection 156 and the gasket 158. The upper valve disk 169 a-,ad lower valve disk 162 are nuts and washers so that they Tray be adjusted and properly spaced so that th--y will seat alternately on the si-irfaces 14$a and 154a, respecti-,rely, as the rod 164 is moved down and Lin. The upper en,4 of the rod 16J, is r) 0 connected to the cyader rod 66a of the cylinder 66 by means of the couplin.@ 63 -and actuatin.a system as illustrated in Fll-'-S. 3 and 4 and as previously described are utilized to provide the reciprocatin@ movement desired. It has been found that the eirbodiment of the inven- 55 tion illustrated in FIGS. 5 and 6 and just described works better - @vith certain Tnaterials and that the embodiment of F-TGS. 1 to 3 works better with others. When the lower valve disl@- 1-62 is seated a.-ainst the !onver seating surface 150a, as shown in FIG. 5, the f[ow ol. material in the 60 valve chamber 143 to the duct 56 is stopped and @naterial in the f,--- ding compartment 3-11 tiows into the chamber 143 around the upper valve disk 160 throu.-h the opening 140. Of course, the rate of this flow is dependent on the same 6r) factors, some of which were previously mentioned in connection with the first eirbodiment. The rod 164 -and valve disks 160 and 162 are then moved rapidly downward by the cvlinder 66 under actuation of a system such as shown in FIG. 3 or 4 il-ntil the 70 L,pper valve disk 'A60 is seated a.-ainst the surface 143a closin.@ oli the flow into the chamber 148 from the f--ed. ing compartment 34. The lower valve disk 162 is then -away from th.- seat and material ilow@s fron, the chamber 143 into the di,-et 56 at a rate determined by many factors 75 45 @ secured on tne threaded valve rod 164 by Pieans of the oi. disks 200 and 202 are positioned to altemately seat in includin@ the ones previously mentioned in connection with the first embodiment. Air leakaoc between th-- feeding cornpartr.,ient 34, the valve chamber 143 and duct 56 during the up and down movements of the rod and valve disks is minimized by the rapd movement of the disks as well as compaction of the material above and below the disks. If the air pressure in chamber 143 is greater than it is in the feeding co-@ppartment 34 and hopper 22, a small amount of air .vill flow upward from the chamber into these areas. As before mentioned, the n-ajor,'@ty of this flow will take place to the left of the baffle 41 which is the path of least resistance and will then pass out to the atmosphere through the cotton vent cloth 42b and expanded metal screen 42a. Bv adjustiig the inteivals of time during which the valve disks ren-iain in either the up or down position, the flow rate can be accurately controlled. Also, the disks can b-- moved at a high speed because of the cushionin@ action of the valve disks as they are seated alterrately. Additionally, the vibrations caused by the rapid reciprocal movement of the valv.- mechanism aid in preventin.- materials from bridging or building up in the valve chamber its-.If, the feeding compartment, and the upper valve disk. To aid in f-lushing the material into the duct 56 from the chamber 148, an air line is connected to the interior thereof in a manner shown in FIGS. 3 and 4 with the slight difference in connectioii in that the Rushing line is connected to the line 80 or 30' instead of 78 or 73' so that the flushin.u air is directed iito the chamber 148 when the rod and valve disks are in the do@,vn position, as illustrated in FIG. 6. Referr;n.- now to the embodiments illustrated in FIGS. 7, 8 and 9, when it is necessary to feed material i.,ito a flow duct which is at a great pressure differential, e;ther higher or lower tha-ii the pressure in th.- material hopp-.r, it may be desirable to provide reciprocal vaive mechanisms having tbree, four or more resilient valve disks. FIG. 7 illustrates an embodin-lent having three resilient valve disks 200, 202 and 204 which ar-- secured i@i concentric spaced apart relation on a reciprocati-rig valve rod 206. The valve disks are secured on the rod in the proper spaced relation by means of the nuts and washers 293 and be adj-,sted to provide for proper seatin- of the valve disks and to compensate for wear. The up'per pair an upper valve chamber 210 in a manner similar to that described in connection with the embodiment of FIGS. 1 and 2. The chamber 210 is provided with an internal generally conical upper seatl-ig surface 212 Lipon wh-icti the disk 2,00 seats when the rod and valve mechanism is in the up position and is provided with a lower internal generally conical st-irface 214 upon which the valve disk 202 seats when the rod and valve mechanism is in the downposition. Thechamber2lOisprovided,,v:thag.- nerally cylindrical mid-portion 216 of greater diameter than the valve disks 200 and 202. Tlere is provided ad,;acent the lower end of the chamber 210 another cj',.amber 218 which is similar in construction to the chamber 143 of FIGS. 5 and 6. The chamber 213 is provided with a generally cylindrical midportion 220 of a diameter smaller than the valve disks 202 and 204. The portion 220 is joined at its upper end to the lower end of the s@-ating surface 214 and the 1 ower end of the chamber 218 is provided with an outwardly projecting generally conical lower seating surface 222 which forms a seating surface -'Lor the valve disk 204 when the valve mechanism is in the up position. The lower end of the seating surface 222 is joined to a generally cylindrical chamber 21-4 having a diameter greater than the valve disk 204 so the d-@sk can move freely therein. The lower end of the chamber 224 communicates viith the interior of a flow duct 56 so that naterial in the chamber 218 may enter the duct and be carried away by the air stream therein when the lo@ver valve disk 204 is in the
[6]down position, as shown in FIG 7. Thiis, the upper chamber 210 with the valve disks 202 and 2@a4 alt-.riate'iy scatin- agaiiist the surfaces 212 and 214 is s-milar in construction to the embod;ment oll FIGS. I ard 2 anci the lower chamber 213 with the valve disks 202 and 25)4 alternately scatin,@ against the surfices 214 and 222, respeztively, is similar i@-i construction and operation to the embodiment of FIGS. 5 and 6. The upper end of the upper chamber 210 is connected to the IoNver etid ol@ a feediTI.conipartment 234 attached to a r@iaterial feed ho,-)I,,cr 22@@ in a manner similar to that d--scribed in the precccl;r@,- embodiments. The upper end of the rod 206 is coririec'Led to the end of a cylinder rod 66a of an air cylind--r 65 through a couplin.- 68 in order to .1)rovide ree-1procating movement of the rod and valve disks. A syslem for actuatin.- the cylinder 66 similar to t'@ics.- of FIGS. 3 @ind 4. m,Ly be utilized to control the actuation of th-, rod and valve disks. When the rod and valnic d-'@sks are in the down pos'tion ol. FIG. 7, material -in the hopper 222 ,,,nd feeding compartment 2314 flows into the ut)-,)cr cb.,i,-@ibei7 2i@0 around the disk 200 but cannot flow from the chamber 210 i-,to the chamber 218 becq@use the valve disk 202 is scalled on the surface 214. Material in the lower ciaamber 218 feeds into the duct 56 around the valve d-'@sk 204 which is b,-Iow the septin- surfac.- 222 in this positio-Ti. The rod and valve disks are then moved to tic up position rapidly and the upper disk 200 seats o-@i the surface 212 shutting off the flow of mat--rial into the upper chamber 210 from the feed compartrrent 234 and alq-o Llie IoNver disk 204 seats against the surface 222 shutt-in,- off the flow of material into the duct 56 from the @lower ctiamber 218. Since the valve disk 202 is not seat.-d on th-- siirface 214 at this time, material in the chamber 210 flows into the lower chamber 210. The flow rates of r@iater'ial from the feedin,@ copipartment 234 into the tipper chariber 210, and from this chamber into the lower chamber 218 and then into th-. duct 56 for transportation in 'Lhe air stream a-c gov--rned by various factors includin- those mentioned in discussing the previous embodiments. In applicat@'@ons where very light material is bcing fed and high pressure differentials are involvcd, either pos;tive or negative, bctween the material hopper and the flow duct, it has been found that the embodiment iilustrated in FIG. 7 works very well. Problems in feeding low density material into or out of hi,-h pressure env;ronments are encountered because of the amount of air flo,,v from hi.-h to low pressure when the valve disks are movin.-, and this is sufficient to virtually s',op the flow, if in a ro -verse direction, and to rapidly dump a l@irge quantity of material in the system with consequent clogg;ng if the air flow is the same direction as the rpaterial flow. For this reason, the use of the cham-ber Zig in series with the chamber 213 in a single feed mechanism provides a means for providing a series of stepped pr,-ssur-,-raclients in wiaich the pressure differe@itial across any one of the valv-- disks is reduced so that the amotint of air flow around tiie disk during its movement is not ob-ectionabl,-. Ftirthermore, with rapid rr@oiement Of i the valve disks, air in the dtict S6, at hi.-h pressure for instanc.-, does not have tinic e@ioti.-h to reach the upper disk 200 before it seats and then after the d-sks are seated the pressur,- dii-ierential in the chamber 210 bleeds ol-I slowly into the compartr@ient 234 withoat -reatly re@d.ucing the downiqow of material as it woiild if only a sin.-le valve chamb-.r and pair of valve disks were used ' In eiTecIL, the average pressures in the chanibers 210 and 219 are between the presstires in th.- duct 56 ar@d feeding compartmeiit 23@l, and the pressure diiterenc-. betvicen any two adjacent areas in the ',ceding path of the material is smaller tjiar. in the case of a feed chamber between ihe duct and hopper where a high pressure d:@fierential is nec,-s.@ary. R--.L'err-.,'ng now to FIGS. 8 and 9, where very high 3,197,261 12 pressure dieterentia'ls are reqtiired b-,tween the hoppers 322 and feeding compartments 334 an,d the flow duct 5C,, t@ze@- valve c-hambers 3@',I@')A, 34,3B a-id 14'o have bee@n u,'ilized in series to further rcduce the pressure differential b--'Lween th-- ad;aceit areas in the rath of rqaterial fi'o@,,v. In the cpibodimer.-t of F@TG. 8, fotir valve disks 36@9, 36' 3G@2 apd 366 arc atta,- hed to a single rod 368 which is connected to the piston rod C3raa of the actuating cyli.-iC@-,r 66 by the cotipl;n,- C@3. The chamber 34@9A 10 with the vilve d-isks ZC@'i a.@id 3(il@ and the chamber 348B with ti-ic dis'@-s 364 and 36,5 bo@lh are sirqilar in oi)eratic-i ai-id constructio-ii to the chamber 43 and valve d-sks 60 a-@id 62 of the embodiment ilIListrated in FIGS. I apd 2 and previously described. The chamber 149 with 15 associc-,t,-d v,-Ive d-isks '-;Ic,2 and 364 is siniilar in operaiion ,i7id co-.-istrtiction to ',he chamber 143 and disks 160 and '62 o4 t',e embodiment illustrated in FIGS. 5 and 6. The cyl@:iider 66 may be acti-iai,-d by a system of the type ill-.Istrated ;n !- '!G. 3 or 4 -,ind previo-,isly described in the 20 sp.-cification. Wi'ien the rod :@ILS and valve disks are in the down 'tio pos@ -.i sbown in FIG. 8, material flows fro.-n th.- feedina compartment into the upper chamber 3e@9A. Material cannot fow iro-,-n this ch?@rr@bcr iiito the middle cham25 bcr '.43 becatise the valve disk 362 is seated. Material f-lows j'roiii the chamber 143 i-ito th-. lower chamber 343B but cannot '.ow tlierefrom into the duct. V@/i'ien the rod 363 is moved to the up position by thecy'@iid,-r a-id actuating systen,, -naterial flows froni the 3o feed@.r.- -.ompartment 33d into the urt)er cbairber 34'A, bi-,t malerial cannot flow from this chamber into the middle chamber 143. Mat,-rial cannot flow fro@n th,chamb@-r into the lo,@@,er chamber 343B, but does flow frorii the chariber 343B into the duct 56 for tra.,isporta@95 tion in the iir streani. 'Ry placi.-@g in effect three vilve chambers with valve disks which alternately seat therewith in series between the feedii.@ comt)artment aid the dlict, it is poss,.ble to successfully feed -,,ery fine or light materials from a 40 re.oion of v-@ry high to very low pre-cstire or vice versa since the pressure differential between any two adjac-@nt areas aloiig the path o'L materiil f,ow is reduced to a workable level. It has also been found that when operating at high pressure differentials between adjacent 45 chambers that long,-r pericds of dwell with the valve disks in the seated position ire desirable when the pressure differen@ial is coi-inter to th@@ direction of material flow i)ccause of a sliphtly lon,@er time required to eqlialize tic pressure before material effectively starts to flow under the effect of gravity. The converse, of course, is true 50 hen the p-essure differential is v,,ith the direction of IV material Piow to prevent dumpidg of lar@ quantities of material ra-nidly i@ito the system which @emi.-ht momentari.7y clo- it up. 55 The embodiment of FIG. 9 is similar to FIG. 8 except that the lower valve disk-s 364 and 3-56 are connected to a separ,,,te rod -z63A which is actuated by a separate air c3,linder ut3A. Th,:s construction allows greater ficxibility of co-nt@- ol of the meclianism since two separate actliation 60 systenis can be synchronized to opera' the cylinders 66 Le and 66A. There is illustrited in FIG. 11 anoth@-r embodime@it of a. system for fe--div@ and transporting materials v,,hich systepi is -indicated '.aen,-ra'Ay by the reference nurreral 6- 490. This system is esp,-cially v;ell siiited for use with low press,.,ires and is relp@tively s@:mp'@e in co-@istruction, thus r@iakin.- it econop-iical to manufacture and install. The system 403 incluldes a material hopp.-r 4,4j2 into vvhicli 70 quantities o-' sand o- other mat@-rial 404 to be transt)orted ar.- diimped. The hopper 402 has sloping walls conver.@in,- inwardly to form an outlet 406 at the bottoni leadin.- to a feed chute 4@oo' which is con.,iocted to the outi'ct in any su@itable rfian:,er such as by welding or by 75 a 'fla-q,-e ar@d bolt co,@istructiop as illustrated. The lower
[7]13 end of the feed chute 103 angularly intersects with a feeder unit indicated -.cr@eraHy by the numeral 410. The feeder unit 410 is preferably constructed of several sections of round pipe and comprises an upper section 412, an intermediate section 414, and a lower section 416. Theuppers@-ctionisprovidedwithatopplat,-4.13 for mouiit;na an actuating cylinder 42,3 which has a piston rod 420a and is siriilar to the cylitider 66 previotisly d,-scribed and which niay be controued by a control system such as illustraled in FIG. 3 or FIG. 4 and described above. The lower end of the section 412 is provided with a flan.-e 422 for joinin.- this section to the inter @mediate sect:,on 414 by means of bolts 424. T'he intermediate s.-etion 414 is provided with upper and lower end flanges 426 and 428, resp,-ctively, wilh the upp-@r flange 426 facir@g the flange 422 of the upper section 412. Between aiese two Ranges there is provided an orifice plate 430 vihich riay be constructed of steel pl@ate and has a ce.@itral flow opeqin.- or orifice 432 defined therein. A similar orifice plate 42-4 having a central 'low opening or orifice 436 is positioned between the lower end flange 423 of the intermediate s,-ction 414 apd an upper end f.ange 433 of th@-- lower section 416. These two flanges and the orifice p.ate 434 are held to,@efrier by suitable means slch as bolts 440 and the lower end of the lower section 416 is provided with a lower end flan,-e 442 which is suitably attached, as by bolts 443, to tl-,e top plate 444 of a lower hopper 446. The top pla'Le 444 is pro,,,ided with an opening 450 aligned with the lower section 416 in order to allow material to flow i-iito the hopper 446. The feed--r unit 410 is provided with a reciprocal valve mechanism actuated by the cylinder rod 420a comprisin.a an upper valve disk 452 and a lower val-,7e disk 454. These disks are preferably of resilient material such as rubber or tn-- like and are positioned in spaced apart relation on a threaded valve rod 456 which is attached to the end of the cylinder rod 420a by means of a flexible couplin- 458. The disks are secured on the rod 456 by means of nuts and Nvashers in a convenlional manner. In order to prevent a large build up of material on the upper surface of the valve disks, there are provided conically shaped collars 450 which are positioned above the disks. Th.- lower hopper 446 is provded with sloping side walls forminan openin- 462 at the bottom of the hopper to v,,hich a vllrtically extending nozzle 464 is connected. The noz7!e 464 is connected to a source of air pressure such as a blower 466 or the like th@- ough a pipe 468 and elbow 470 ' CentraJly positioned within the hopocr 446 and coaxial with the nozzle 464 there is provided'a vertically disposed, upwardly extending flow dact 472 for ,transporting material to a desired location. An end collar 474 at the lower end of the flolv dact 472 has tknered inner walls and is spaced vertically upward from the nozzle 464 so tlat high velocity air from the nozzle entrains the material in the hopper ar@d carries it upward in the flow duct to be trans-oorted to the desired location In operation of th.- system, the material 404 in th, hopper 402 'Llows downwardly throu.-h the feed chute 403 into the upper section 412 of the feed-.ng device 410 and around the valve disk 452 through the orifice 43Z into the intermediate section 414. The rate and amolnt of ftow is depende-,it on m@,ny factors includ;ng the flowabi'ity of the material, the level or amount of material ' in the hopper, the size of the feed chute, upper section, valve disk and orifice diameter, and the amount and velocity of -apward travel and duration of dnvell in the upper position of the upp--r valve disk. lxthen the valve mechanism moves donvnwardly the upper valve disk 452 seats on the oiifice plate 430 to prevent flow from the upper section 412 to th6 ;ntermediate section 414 and, at the same ti.-ne, the lower disk 459 moves downwardly away from seating engagement with the lower orifice plat-. 434 to permit the material in the intermediate section to flow into the lower 3,197,261 14 hopper 446 for transportation in the air stream. This rate of flow is likewise dependent on several factors as discussed above. The material in the hopper 446 flows toward the bottom of the hopper where it is picked up by the air stream from the nozzle 464 and is carried up the flow duct 472. The rate of flow a,-ain is dependent on many factors includin.@ the particle size, density and flowability of the material, the amount of air pressure available from the 10 blower, the distance between the lower collar 474 and the nozz'@e, and the shape of the internal surface of the collar and nozzle. When it is desired to stop the flow, the feeder mechanism 410 is shut down with its valve disks in the position 15 shown in FIG. 11 and the material remaining in the hopper 446 is carried out through the flow duct 472 at which time the blower 466 is shut down. When it is desired to start the flow of material, the feeder mechanism is again placed in operation and the blower is started. 20 As was previously discussed in connection with other embodiments the rate of flow through the feed mechanism can be accurately controlled by adjusting the time periods of dwell in the up and down positions of the valve mechanism. The use of standard round pipe and flat orifice 25 plates makes the feeding mechanism simple and economical to constr-uct and, while it,does not possess some of the advantages of the other embodiments, the arrangement shown in FIG. 11 will work well with relatively free flowing material such as sand. Also, orifice plates 30 having various size openin,@s can easily and rapidly be installed in the feeding mechanism to obtain the desired flow rate. Air flow from the lo-,ver hopper 446 into the feeding mechanism when the valve disks are in trans;.t between seating is of little conseq-uence and is minimized 35 by.utilizing high velocity movement of the valne mechanism. Re@@lerring now to FIG. 12 there is illustrated yet another embodiment of a feeding device constructed in accordance w,@th the features of the present invention and 40 indicated @encrallv bv the reference numeral 500. The device 500 is d--signed to feed a variety of different rnaterials at a wide range of -flow rates encompassing minimur@i flow rates as low as 0.1 lb. per hour. The device will deliver r@iaterial at relatively constant flow rates over a wide ran-e of values and is extremely useful in provid45 ing an even flow of material wherein momentary surges in the 'low rate would be critical to ',he operation of a bler@din.- or mixing type transport system. The device 500 inclildes a material receiving hopper @-@02 into which quantities of sand 504 or other material 50 to be transported is dumped Lrom time to time. The hopper SP;2 is s6mewhpt similar to the hopper shown in oiher fig,,ires o'L the drawings and previously described in this sp.-cification and includes a sloping bottom wall 504 which is joined to side walls 506 and a vertical front 55 wall 508. The front wall 503 is provided with a discharge openin.@ 50-Sa at the lower portion thereof so that m-@terial in the hopp.-r will 'tlow downwardly and outwardly through the opening into a generally rectangular feedin.- chamber 510 disposed adjacent the front wall of 60 the hopper. In order to control the flow of material from the hopper 502 into the feeding chamber 510, there is provided a moitable gate 512 which may be secured to th@- -'Lront wall 509 in a plurality of different positions by means of wing r@ut and bolt assembi:@es 514. By lowering 65 or raising the gate 512 the effective area of the opening 508a and hence the feed rate to the chamber 510 can be controlled. The rectangLIar feed chamber 510 includes side walls 516, a top wall 518 and a front wall 520 which may be 70 constructed of transparent material such as glass or plastic in order that material in the chamber can be viewed from the outside. The fr6nt wall 520 is removable from the structure and is held in place by a plurality of bolts 522 and a gasket 524 is prbvided fot effecting a seal between 75 the front wall and the other walls of the chamber. A
[8]baffle 526 is provided in the feed chamber to prevent material from building up a,-aidst the front wall 520 and the baffle is also preferably constructed of transparent material as not to restrict the view into the chamber. The lower end of the f-,cd chamber 510 is generally open to perriit material in the chamber to flow downvve-.rdly into a valve chamber 530 which is disposed directly therebelow. The upper end of the chamb-,r 530 is provided with a mounting rin.- 532 formed of an an.-le and having a horizonal -iqan.-e which is bolted to the lower erd of the hopper 502 and a bottom wal'i 534 o.f tl-te fc,-d chamber. The bottom wall 534 is provided w'ith an openin.- 534a to allow material to fiow downwardly into th-valve chamber and a -asket 536 is provided to eitect a seal between the flan.-e of the motinting rin.- 532 and the bottom wall and bottom of the hopper 502. The chamber 530 is constructed of an upper port:@on 538 and lower portion 5-'IO having fl,- @n.@es 53'@a and 540ct, respectively, which are bolted tot.,etbor wilh a gas!-et 542 therebetween to eff--ct a seal. The iipper port-ion 53'0 has a cylindrical low-,r section and an inwardiv di@-ected conical portion at the upper end thereof -,vh:@ch forms an upper, ge-Lierally conical valve scatin.- surface 544. The lower portion 540 is provided with a cylindrical upper portion a-,id a lower, inwardly directed conical r)o@-tion Nvhich fornis a lower generally conical valve seatin-, surface 546. Within the valve cl-iamber 530 there is provided a r.-ciprocally movable valvo member 550 wbich includes an upper resilient valve disk 552 which is spaced i-ipwardly apart from a similar lower resilient valve disk 554. T'@-e disks 552 and 554 are secured on a valve rod 556 wliich is aiial@ly dist,)osed in the valve chamber 530 and extends u,,owardly into the feedin.- chamber 510. The lower portion of the valve rod 556 is threaded to receive a plurality of nuts 553 and -,vashers 559 which are provided to secure the valve disks on the rod i@l the proper spaced relation. As the valve disks or the conical seating stirfaces viear during operation, the spacing of the disks can be adjusted as needed to provide for positive seating between the seating surfices and the disks. - In order to provide for reciprocal movement of the valve element 550 within the valve cbamber 530, the upper end of the valve rod 556 is connected to the lower end of a piston rod 560a of a pneumatic cyl;nder 560 which is mounted on the top wall 513. The valve rod 556 and piston rod 560a are con-iiected together by means of a flexible coupling 562 in order to provide for limited lateral movement of the valve element 550 within the valve chamber so as to effect good seating between the disks and their respective conical s-ating surfaces. When air pressure is sup;lied to the lower end of the cylinder 560, the valve member 550 moves upwardly. As this occurs, the upper valve disk 552 seats against the upper conical seating surface 544 preventing material from flowing into the valve chamber 530 from the feeding chamber 510. During this upward movement of the valve member, the lower valve disk 554 moves upwardly .away from the lower seatin.- surface 546 allowing material in the valve chamber 530 to flow downwardly out througa the bottom outl.-t of tb-I chamber. When air pressure is no longer supplied to the lo@,ver end of the cylinder 560 or when air pressure is supplied to the upper end thereof, the valve member 550 moves downwardly. As this occurs the upper valve disk 552 moves do@.vnwardly tNiay froni seatin.- enga.-ement Nvith the upper seating stirface 544 allov;in.- i-naterial in the feed mber 510 to flow downwardly into the valve chamber 530. Durin.- this do@vnward movement, the lower valve disk 554 moves downwardly into scatiiig ep-a-ement with the lower seating surface 5e,6 shtittin-, off the flow from the chamber out,7,,ardly througti the bottom otitlet thereof. Thus as the valve member 550 is reciprocated witbin the cha;@ber 530 by the cylinder 560, the upper and lower valve disks altemately seat a.@ainst their re,-zpective seating surfaces in the chamber. This alternate seating of the valve disks allows material to first flow into the valve 3,197,e-IE3! chamber irom the feeding chamber and then from the valve chaniber into the systeni ' The flow rate from the cha@-,Iber is dependent on a number of different things ir@c'@uding, type, particle s;ze and flowability of the material r, b@-ing ed, the size of the chamber, the pressure differential betvveen the valve chamb-@r and the feeding chamber aiid the system, the time duration of the upward and downwqrd strol,@es of t.qe valve memb-.r and the time intervals that the upper and lower valve disks are seated 10 a.-a@'nst their respective seats. Directly b--Iow the dischar.ae outlet of the valve chamb-,r 5--,10 ard i.1 commuricat@.on therewith is provided a colleeing chamb-,r which may take the form of an elbow fittin-, 56@-, @,avin-, a Nertically exteilding -enerally cylin15 d@-ical upper sect;on r(j'6 which transitions into ahorizonta'@'ly CLirec'L-,d outlet 568 of reduced diameter. The upper encj of the cylindrical. section 566 is provided with a ring f-lan.-c 566a @vhich is bolted to a siriiiar flan.-e 540b provided at the lower end of the valve cban.ber and a sealing 20 f,:@,sket 570 is disposed botwe-.n the fiar.,-es to effect a tight seal tli-.r@-between. Th@- o@,itlet S@<8 is connected to a flex-'ble delivery tube 572 by means of a trans@tion fitting 574 and the delivery t@,ib-- 572 is coinected to a trapsdo@-t duct 576 in whicb a 25 ilo@,v;,-i- air stream is t)rovided for transportin.a the solid iiatc@rial as it is i-@itroduced ipto the duct throu-.h the delivery t@,ibe. Preferably the delivery tube 572 ind fitting 574 are cor@structed of flexible plastic material in order thpt the material ftow r@iay be visually observed therein. @o '.In order. to n@ ova material from the elbow fitting 564 into the transport duct 576 at a relatively eveii discharge r,-,t-., there is provided apneiimalic nozzle 580 which is disposed with,@n an openin-. 5' .2 provided in the elbow fittin.- opposite and axially aligned with the outlet 568. 35 The nozzie 590 is a-,,,ially movable within the openin- 582 so that it can be positioned in the most advantageous pos-ition to best move the material in the elbow fitting out throligh ttie outlet 5,53, discharge ttibe 572 and into the transport duct 576. The most advantageous position will, of course, be dependent on a number of factors including the type, particles size and flowability of the material, the air pressure suppl@'@ed to the nozzle and the various pressures prevailin.- in the valve chamber, elbow fitting and the transport duct and the amount of material discharged into the elbow fitting each time the valve member 550 moves 45 upwardly to the position shown in FIG. 12. It should b.- noted that the outlet 563 and delivery tube 572 are both of much smaller cross-sectional area than the cylindrical sectioii 566 of the elbow fitting 564. Thus, whe@i material in the valve charrber 530 is discharged into 50 the elbow fitting 564, it cannot immediately flow in a lar.@e surge into the trarsport duct 576. The nozzle 550 provides for moving the material at a relatively even fiow rato into th-- transport duct until the material in the elbow f-tt@'@ng is n.-arly exhausted at which time the valve member 55 553 again moves upward to dischar,-e another quantity oj' naterial into the fittin.- from the valve chamber. The add;tion of the elbow fittin.- and air nozzle evens out the fiow of material into the transport duct and prevents s@,ir,@es of material into the system each time the valve 60 member rr@oves upward to dischar-,e material out of the valve chamber. The a:r Tiozzle, in addition to smoothing out the flow, also aids in starting the flow initially and -reatly increases the ran,-e of flow rates that can be obtained with the sys65 tem., It has been found that flow rates as low as 0.1 lb. per hotir are obtainable and materials having low flo,,vability characteristics or high angles of repose can be utilized with the apparatus. Accurate control of flow rates is readily obtainable by ad,;usting the air pressure supplied 70 to the air nozzle a-@id by adjustin.- the position of the nozzle in ti-le elbow fittin@ In order to aid the fl-o-w of mat--rial from the hopper 502 into the feeding chamber 510, the bottom wall 504 of the hopper is p,,@ovid--d with in aerator assembly 580 75 and an air operated vibrator 532. The aerator assembly
[9]17 590 includes an enclosure 534 which is suppeed with compressed air froni an air line 536. The bottom wall 504 of the hopper is provided with a plurality of holes 504a and above the holes is provided a screen 583 havin.- a mesh fine enough to prevent the material in the hopper from vassing throu.-h while allowing air to flow up-ward from the enclosure 584 into the hoiaper in order to aerate and a.@itate the riaterial so it will flow freely from the hopper into the feed chamber 510. Thp- vibrator 582 is s,,ipplied with comprp-ssed air from a line 590 and operates to vibrate the hopl)er 502 and connected as-semblies to furlher aid in causing the material to freely ,Liow from the hopper and feed chamber. The air lines 586 and 590 are co--nected to -a common suoply line 592 and re.-Ula'or valves 594 and 596 are provided in the liies 5'.6 and 590, respectively, to re,@ulate the air pressure supplied to operate the aerator 590 -and vibrator 582. The comriion sui)ply line 592 is connected to an upper @bravch line 593 which supplies compressed air to the iipper end of the air cylinder 560 in order to cause a downward movement of the valv.2 element 550. The ii,)per branch line 598 is connected to one outlet of an a;r valve 690 which is electrically actuated by a soleiioid v,,inding 602. The lower end of the air cylinder 563 is connected to an alternate outlet of the solenoid valve 600 by.u,cans of a lower branch line 604; and when the valve slipplies compressed air to this branch, the valve memb--r 550 is moved unwardly to the position shov,,n in FIG. 12. Compressed air is supplied to an inlet port of the valve 600 from a stipply manifold 606 which in turn is conr-ected to a suitable source of compressed air such as an air compressor or compresse-d air tank (not shown) through s-.@ipply line 608. Th5 supply line 603 is provided w;th a shut oiT valve 6IG for cutting off the air stipply to the system and a re.-ulator valv-- 612 for adjL,stin@- the a;r pressure into the supply m-,nifold. A press-.-ire gauge 614 is alSO Drovided in 4Drder that the re,@uiator valve 612 can be adjusted to obtain the proper air pressure for th.- systei-.. The valve 600 is of the sprin.- return type and ivheil no curr.-Tit is supplied to the solenoid 602, the valve is positiolied to supply air from the supply manifold 606 into the lo-,,@,er bl-an-.h lin-- 604 to ma;ntain the valve member 550 in the uj)per position. While in th,s position, the upper e@id of - the cylinder 560 is exhauste@ to the atm@ osph-,r-- thrcu,-h the upper branch line 598 and out an exhalist port 616 prov,.'ded L-i the valve 600. Also, the aerator ass-,mbly 5&f) aid vibrator 582 are inoperative durin@ this time since their suppiy line 592 is conn-.cted to the upper branch I;ne 593. '@t should also be noted that a lubricator 6-'E$ is pos@tioned in the upper branch line 5,90 i.p @crdcr to ILbrizate the air cyl-l-@ider 560. the -solenoid 682 is electrically energized, thpval,ic 6'og is moved to connect the lower brancla line 604 to the atmosphorc through the exhaust port 616 and the upper branch I.Ine 59T3 to the supply line 686. NVhen this h,@ippens, con-.pressed air is supplied to the upper end of the cyl@nder cau@ing the valv,- member 550 to move e@ 0"7, ri@7vard and allow material to flow into the valve chamber 53fj f-rom thp- hopp@@r 5@'o2 and feed cha-rnber 510. Air pressure is also supplied to 'Lhc@ aerator assembly 580 and 'b @, vi .,,,or 532 dl,.ring this time to aid the material in freely ,Llowing from the hopper 502 into the feed chamber 5@10 ar-d valve chamber 53,I). As the s,,I@-roid 692 of the valve 6;,10 is ener.-ized a-@id deener-ized f@-om electrical impulses supplied to the solenoid winding, the valve m--mber 550- r@-ciprocates ut) and dowia in th@o valve chamber 530 to alternately seat the valve disks 552 and 554 as previously described. By adjusting the air pressure in the syslem, the desired veloc;ty of travel of the valve member can b-- obtair@ed and by regulating the length of tinie of the electrical impulq-es to the soleio,@d 692 and the inte@- val between successive iir.ptilses, th@- time interval during which either of the valve 3,197,261 disks are seated can be effectively controlled. These factors, among others previously mentioned, estzcblish the feed rate into and out of the valve chamber 530 for any given type of material bein- fed by the system. 5 The air nozzle 5'00 is connected to the main supply line 606 by means of a branch lirte 620. Within the line 629, there is provided an adjustable pressure regulator valve 622 which is adjustable to provide the desired operating pr@-ssure for the nozzle. A pressure gauge 624 is pro10 @ided in order to assist in adjusting the pressure in the iine 620 to the desired pressure. In order to pr@ovide controlling means for supplying compressed air to the nozzle for selected periods of time, a normally closed spiinretlirn type solenoid valve 626 is disposed in the line 620 15 ah-,ad of the regulatot valve 622. When the solenoid valve 6'@6 is electrically energized by an electrical pulse of a pred,-termined time duration, the valve is opened to allow air fiow to the nozzle for the selected time interval an,-,' at the end of the pulse, the valve returns to the closed 20 position to shut off flow to the nozzle. By controlling the air pressure to the nozzle 580, the time interval durin-. which the air pressure is supplied to the nozzle, and the position of the nozzle in the elbow fittin.- 564, the feed rat-, -of material from the elbow fitting inlo the trans25 port duct 576 can be accurately control-led. In order to provde for Rushing out the valve chamber 530 and additionally to aid in starting the iqow of material outof the chamber after a prolonged period of shutdown, a fil,.shing air line 628 is connect-.d between the line 620 30 anid the upper end of the valve chamber 530. Compressed air supplied to the valve chamber 530 from the flushing line 620 aids in c@ausing material in the cbamber to flow out into the elbow fitting 564 and into the transport dlct 576. A solenoid valve 630, similat to the valve 35 626, is disposed within the flushin- line 628 to control the air i'low in the line so that air pressure can be supplied to flush the valve chamber at selected time periods. A pressure regulator valve 632 is provided in the flushing line to control the pressure of the flushing air supplip-d to 40 the chamber and a check valve 634 is provided to prevent a back flow into the flushing line. A sirnilar check valve 636 is also provided in the line 620 leadin.- to the air nozzle 580 to prevent a back flow into the line from the elbow fi'Lting of the feeder. 45 T n order to @djustlbly control thp- fiow rate of material fror@l the feedin.- device 500 into the trarsport duct 576, there is i)rovided an electrically operat-.d timing system refered to g,-nerally by the refererce r-unieral 640. The timin-, system 640 i-Ticludes a Irst timer 6,12 (also labeled 50 tim,-@r #1 on the drawing) which is s-.Iectively adjustable to send a-.i ele@-trical current to the solenoid valve 626 for a selected time duration via an electrical cable. When timer #1 starts on its timing cycle of selected duration, the r@orrially closed valve 626 is opened allowing air pres55 sure to flow to the nozzle 580 and riove the material in - the elbow fitting 564 out into the delivery tube 572 and transport duct 576. The total amount of flow for any -iv,-n material and nozzle air p@-essure is dep,-ndent on the length of the tinie cycle of timer #1 and thp- timer 60 is s,-t so that it will time out whe-ii ihe material in t'@le e'@bow fitt-ng is just about exhausted. The electrical cable 64.,! may ,ilso be connected via a branch cable, 646 to actijate the solp-noid valve 630 for permiiting air to flow into the upper pc)rtion of the valve chamber 530 throu.-h 65 tl-ie f-@,ishing line 628 and thus air the nozzle 580 in moving material out of the valve chamber into the transport duct 4,@@i 6. Timer #1 is elect@rically connected to a second timer 643 (also labeled timer #2 on the drawing) via an elec70 trical cable 650 so that at the end of the timer cycle of timer #1, timer #2 is energized to begin its selected time cycl--. When ti@ner #2 starts its time cycle, electrical energy is supplied to the solenoid 602 of the valve 600 via an electrical cable 650 causina it to direct air pressure 75 to 'che top side of the, air cylinder 560 causing the valve
