US2861840A - Apparatus and method for feeding bulk material to plural supply locations - Google Patents

Description

Nov. 25, 1958- J. w. POWISCHILL ET AL 2,

APPARATUS AND METHOD FOR FEEDING BULK MATERIAL TO PLURAL SUPPLY LOCATIONS 3 Sheets-Sheet 1 Filed Aug. 12, 1955 rlzW L N Nov. 25, 1958 J. w. POWISCHILL ET AL 2,8

APPARATUS AND METHOD FOR FEEDING BULK MATERIAL TO PLURAL SUPPLY LOCATIONS Filed Aug. 12, 1955 3 Sheets-Sheet 2 Nov. 25, 1958 J. w. PowlscHlLL ET AL 2,861,840 APPARATUS AND METHOD FOR FEEDING BULK MATERIAL TO PLURAL SUPPLY LOCATIONS 3 Sheets-Sheet 3 Filed Aug. 12, 1955 dam dado Q53 udu wad hmu mud EU mu 66073.79 IiHmu-ard Nhm h w N2 9 NOm 2am whim 2,361,849 Patented Nov. 25, 1958 United States Patent Ofiice APPARATUS AND METHOD FOR FEEDING BULK MATERIAL TO PLURAL SUPPLY LOCATIONS John W. Powischill, Cheltenham, and Edwin W. Hine II and George Robert Howard, Philadelphia, Pa., assignors to Proctor & Schwartz, Inc., Philadelphia, Pa., a corporation of Pennsylvania Application August 12, 1955, Serial No. 528,082

7 Claims. (Cl. 302-11) This invention relates to feeding methods and apparratus and is concerned particularly with the problem of provision of a system for maintaining a reasonably uniform supply of loose, bulk, material at a plurality of .similar locations from which it is dispensed in the performance of industrial operations. It is in the nature of .a refinement and improvement in the system and features :described and claimed in our copending application, .Serial No. 513,684, filed June 7, 1955. As an example -;of a problem solved by the invention, there may be cited the creation and maintenance within the feed hoppers of .a plurality of cigarette making machines of a supply of .tobacco which is ordinarily dispensed from said hoppers :substantially continuously in the manufacture of cigazrettes.

The apparatus and method of the invention may be :employed as a solution to a large number of feed and :supply problems. Since, however, the primary research on which they are based relates to maintenance ofa supply of tobacco at each of a number of cigarette making machines arranged in a spaced arrangement, it will be convenient to discuss the invention primarily in relation to such problems.

In the supplying of tobacco to cigarette making ma- 'chines from their respective hoppers, there must obviously be maintained in the hopper of each machine a supply of tobacco sufficient to maintain continued operation of the machine. It is Well known to persons skilled in this :art, however, that this does not constitute the total sup- ;ply problem, for it is necessary not only to maintain a .supply in the hopper, but to maintain such supply at a fairly uniform height and amount, which should vary if :at all only within rather narrow limits. This follows from the fact that any substantial variation in tobacco depth in the hopper will necessarily alfect the density and quantity of tobacco fed to the cigarette making machine. It is accordingly an object of the invention to provide a :feeding system which will ensure maintenance of a virztually constant supply of tobacco at the individual hoppers feeding a plurality of cigarette making machines.

In the past, efforts at maintaining such uniformity of :supply have either involved visual inspection together with manual replenishment or control in accordance with 'athe judgment of an operator, or they have involved an effort to accomplish the same type of result automatically; i. e., to feed tobacco to the individual hoppers on a demand basis as feeler or other sensing mechanism indicated the need for replenishment. This type of control is subject to two basic drawbacks. In the first place, it :requires a rather complicated mechanical arrangement, :and in the second place it does not always respond adeiquately to demand, particularly when two or more hoppers differently spaced from the primary source of supply demand material simultaneously.

In contrast to these systems the present invention provides an apparatus and process by which the supply may be maintained at each hopper quite simply within closely defined limits, once the basic supply to each hopper and operation of the individual cigarette machines supplied thereby has been established,

A primary feature and object of the invention has been to provide a supply apparatus and method satisfying the requirements of the art as discussed above.

A further object and feature has been the provision of such an apparatus and method in which the hoppers are arranged in serially spaced relation and are incrementally supplied in an established sequence to provide a uniform supply at starting up and during continued operation.

A further object and feature has been that this system continues to operate, in accordance with the established sequence, through repeated cycles until sensing elements associated with one or more hoppers indicate that the amount of material in such hoppers exceeds the desired amount. In continued feeding of material to the hoppers, the feed to such particular hoppers is discontinued until their respective associated machines have been operated to utilize material to an extent which again requires feed supply. However, during this interruption the feed to the remaining hoppers is continued in the established sequence.

A more specific object of the invention, as compared to the apparatus and process illustrated and described in our copending application 513,684, has been to provide an apparatus and method in which economy and reliability are improved by simplification and improvement upon the apparatus of that application and its principle of operation. To this end, the delivery of the loose material into the individual hoppers from the conveying apparatus which transports it to the delivery locations, is accomplished by deflecting this material laterally into the respective hoppers by the operation of a system of blowers, and these blowers are timed with the progression of the material to locations adjacent the respective discharge zones, so that, by operation of each successive blower for a timed interval following arrival of the leading end of the material adjacent such location, a desired increment may be discharged into each hopper.

As a further object and feature of the invention after delivery of an increment of material to each hopper in the manner discussed above, the material remaining along the entire length of the conveying means is simultaneously discharged by again impelling this conveying means forwardly, while blowing the material laterally from each discharge location into its respective hopper simultaneously.

As a further feature and advantage of the invention, the material is discharged from the leading end of the conveyor into the final discharge hopper by direct deposit, rather than by lateral deflection, and special control means are provided to prevent lateral deflection in case an adequate supply is already present at any hopper location, and to prevent forward feeding of material upon the conveyor into the final discharge hopper, under particular circumstances involving the presence in that hopper of an already adequate supply.

Still further features and advantages of the invention, and the manner in which they have been attained, will be evident from reading of the following detailed description in the light of the attached drawing, in which,

Figure 1 is a plan view of a preferred form of organization of apparatus for practice of the invention,

Figure 2 is a side elevation of the apparatus of Figure 1,

Figure 3 is a cross-section on the line 3-3 of Figure 1,

Figures 4l0 are diagrammatic views illustrating successive steps in the practice of the process of the invention, and

Figure 11 is a diagram of the electrical connections and their relations to the respective cams which control operation of the system.

As illustrated in Figure l of the drawing, the invention is practiced, in the presently preferred form, by feed of the tobacco or other loose bulk material from a supply source by a master feed conveyor 2%} which may be a vertical spike apron, to a transverse conveyor 21 which may be a belt operating alternately in opposite directions to deliver tobacco alternately to conveying means in the form of belts 22 and 23 by which it is fed into positions from which it is discharged into the respective supply locations or hoppers. With a continuing supply of to,- bacco thus being discharged upon conveyor 22, the system will operate as illustrated in Figures 4l0 of the drawing, in supply of hoppers of cigarette making rna chines from this conveyor.

As conveyors 20 and 21 operate to discharge tobacco upon conveyor 22, this conveyor is advanced in the direction of the arrows of Figures 4-9 to cause progression of the leading edge of the deposited bed of tobacco past the locations from which it is discharged to the supply hoppers of the individual machines, as illustrated in plan in Figures 540. In the initial travel of belt 22, it reaches a point opposite the laterally directed nozzle 30 of blower 24, the nozzle discharge being directed across the upper or conveying run of conveyor 22 as illustrated in elevation in Figure 4, to blow the leading edge of the advancing bed of tobacco laterally and into a discharge duct 25 from which it is deposited into the hopper 26 which supplies the. first cigarette making machine of the line.

As the tobacco is fed forwardly by conveyors 20, 21 and 22, the leading edge will be brought into the successive range of blowers 27,28 and 29, which serve to deflect successive increments into ducts 32, 33 and 3d and hoppers 35, 36 and 37, respectively. The operation of the blower 24 is timed with advance of the tobacco upon conveyor 22, so that the blower starts up at the time the tobacco reaches the location illustrated in Figure 5, and is continued in operation for a time which may be equal to the time required for a given portion of the conveyor run to travel from a position opposite blower 24 to a position opposite blower 27 Thus, as the conveyor run travels forwardly for this distance after the blower starts up, the body of tobacco being fed forwardly during this interval will be fed to hopper 26.

After the Hopper 26 has received this desired increment, blower 24 will be stopped, with the result that the leading edge of the deposited bed of tobacco will again advance during continued feed to and by conveyors 20, 21 and 22 until this leading edge reaches the position of Figure 6, opposite blower 27. This blower 27 is then started up. to deflect an increment into duct 32 and hopper 35, after which blower 27 is stopped and the leading edge allowed to progress forwardly to the position of Figure 7. In similar manner, each of hoppers 35, 36 and 37 will receive a desired increment of tobacco by operation of its associated blower. for a predetermined time after the leading edge of the tobacco reaches its associated blower, these blowers being operated in the proper timed sequence to efiect this lateral discharge, as illustrated in Figures 5-8,

After performance of the discharge operation illustrated in Figure 8, and the stopping of blower 29, the tobacco will continue to be fed forwardly by conveyors 29, 21 and 22 until it reaches the position of Figure 9 and spills over from the leading end of conveyor 22 into discharge duct 3% and hopper 39. After this discharge into hopper 39 has continued for a time suflicient to discharge into that hopper an increment similar to that discharged into each of hoppers 26, 35, 36 and 37, Phase I of the feeding cycle will be completed, and conveyors 2t), 21 and 22 stopped prior to commencement of Phase 11. During this phase, no further tobacco will be fed to conveyor 22, but the body of tobacco 4 remaining on conveyor 22 will be discharged into hoppers 5, 36, .7 and When the system reaches the condition illustrated in Figure 9 of the drawing after discharge of tobacco into hopper 39, there will be contained on conveyor 22 a mass of tobacco approximately equal to the total of that which has been discharged into the hoppers during Phase I. Furthermore, there will be approximately equal amounts at locations on conveyor 22 rearwardly of blower 24, between blowers 24 and 27, between blowers 2'7 and 253, between blowers 28 and 29, and in advance of blower 29, respectively, these equal amounts being also equal to the amount discharged into each individual hopper during Phase I.

To accomplish the feeding operation of Phase II, this tobacco remaining upon conveyor 22 is discharged simultaneously into the respective hoppers, and this is achieved by again starting conveyor 22 to feed the tobacco, forwardly while simultaneously operating each of blowers 24, 27, 28 and 29 as illustrated in Figure 10. During this phase, conveyor 21 may be operated in the opposite direction as illustrated in Figure 10, for a purpose to be discussed hereinafter.

In addition to the abovediscussed general features of the invention, it includes features by which the feed of material to any given hopper according to the system discussed above foroperation of Phase I or Phase II of the feeding cycle is interrupted Whenever the supply to the particular hopper accumulates to the point where such further feed is undesirable. Thus, in performance of the operation illustrated in Figure 6, by which tobacco is fed to duct 32 and hopper 35, when hopper 35 has received a quantity of tobacco in excess of its requirements, the operation of blower 27 will be skipped When the cycle reaches the normal point for such operation, with the result that the body of tobacco which would be discharged laterally into duct 32 will instead be fed forwardly into the position illustrated in Figure 7 during this part of the cycle. Since the timed operation of the blower 28 does not occur until a point in the cycle of operations later than that at which the blower 27 is stopped, the blower 23 will not be started, in this instance, until the advancing forward end of the body of tobacco, has reached the position illustrated in Figure 8. Blower 28 will operate at this time (assuming that its hopper is not yet sufficiently supplied), but the forward end of the body of tobacco, which normally would have been discharged into duct 32, being in advance of the positions of both blowers 28 and 29 at the time blower 29 is started, will continue in its forward movement and be deposited into duct 38 and hopper 39.

In a similar manner, it any of hoppers 26, 35, 36 or 37 is already fully supplied when Phase II of the feeding cycle is started, its blower will be cut out with the result that no tobacco is received. The operation of the conveyor 22 is maintained in Phase II for a time sulficient to discharge any tobacco which may remain on the conveyor because of discontinuance of operation of one or more of the blowers, into duct 38 and hopper 39.

In order to prevent hopper 39 from becoming overloaded, the movement of conveyor belt 22 and the entire conveying system comprising conveyors 20 and 21 may be interrupted, after completion of the step illustrated in Figure 8, and without feeding any tobacco forwardly from that position to the position of Figure 9. Thus, in spite of the fact that hopper 39. occasionally receives an increment of tobacco in excess of its normal supply, by reason of the interruption of one or more of the blowers as discussed above, this fact may be compensated by interruption of conveyor 22 in this manner.

In the foregoing discussion, we have considered the operation of conveyors 2t), 21 and Zn, in their relation to practice of the invention in feeding tobacco to the hoppers in the successive phases, as though this involved the entire feeding system. As a matter of fact, in the preferred practice of the invention, a plurality of lines of cigarette making machines may be supplied simultaneously. Thus, as illustrated in Figure 1, after Phase I of the feeding cycle has been completed with respect to conveyor 22 and its associated blowers and hoppers, conveyor 21 will be reversed as indicated by the arrows, and Phase I will be performed in feeding of tobacco to conveyor 23 and its associated blowers 42-45 and hoppers 46-50, in exactly the same way as discussed above with respect to the deflection of tobacco from conveyor 22 to its associated hoppers during Phase I of the operation involving conveyor 22. By this sequence of steps, Phase II will be accomplished in feeding the remaining tobacco on conveyor 22 to its associated hoppers at the same time that Phase I is accomplished with respect to conveyor 23 and its associated hoppers. Thus, the system is operated in alternate performance by conveyors 22 and 23, and the feeding operation progresses with respect to both of these conveyors and both phases in alternation, and with only a brief interruption between successive phases.

Suitable side panels 53 and top panels 54 (Fig. 3) are provided along the sides and above the respective conveyors 22 and 23, in order to minimize loss of tobacco and prevent turbulence in directing the tobacco into the desired locations. The side panels adjacent the discharge ducts 25, etc., are of course interrupted at the locations of these ducts to permit discharge of the tobacco laterally into the ducts and the cigarette machine hoppers, as illustrated at 55 in Figure 3.

In the preferred practice of the invention, the apparatus is electrically timed and controlled by the operation of a synchronous motor 60 (Fig. 11) which drives through its shaft 61 a plurality of timing cams, and these timing cams control the operation of individual motors operating the various conveyors and blowers discussed above. These timing cams control the operation of the motor which drives master feed conveyor 20 through switch 62 which closes contacts 63 and 6-4 in the circuit of that motor. They also control the motor driving conveyor 21 in the direction of conveyor 22 (we will arbitrarily designate this the forward direction) through switch 65 which closes contacts 66 and 67 in the circuit of that motor, and similarly close switch 68 controlling contacts 69 and 70 in the circuit of the motor driving conveyor 21 in reverse at the appropriate point in the cycle of operations. Through switches 73 and 76 and contacts 74, 75, 7'7 and 78, they also control the timed operation of conveyors 22 and 23 whose motors are controlled through circuit connections including the contacts 74 and 75 and the contacts 77 and 78, respectively. They also control the individual motors of the blowers 24, 27, 28 and 29 which have been designated as BL 1, Bis-2, BL3 and BL-4, respectively, associated with conveyor 22 and blowers 42, 43, 44 and 45 designated as BL6, BL-7, BL8 and ISL-9, associated with conveyor 23, to insure the proper timed operation of these blowers in the desired sequence. Through relay-operated switch groups 79 and 82, they also control the simultaneous operation of blowers BL-1, BL2, BL-3 and BL-4 in Phase II of the operation with respect to conveyor 22, and of blowers BL6, BL-7, BL-S and BL9 in Phase II of the operation with respect to conveyor 23. For the sake of convenience of description the machines associated with the hoppers receiving their tobacco from the conveyor 22 have been designated as A-1 through A-5, respectively, and the corresponding machines receiving discharge from conveyor 23 as 34 through B5, respectively.

While various combinations of timing features may be adopted within the principles of the invention, it will be convenient for us to discuss it in relation to an operation in which, in one revolution of the shaft of the synchronous motor 60 operating the timing cams, Phase I of the feeding operation is performed in delivery of tobacco through conveyor 22 to its respective hoppers, and then Phase I is-similarly performed through conveyor 23 to its hoppets, while Phase II is being performed with respect to conveyor 22. During subsequent operation, Phase 1 will then be performed through conveyor 22 during the first 180 of rotation while Phase II is performed through conveyor 23, and during the subsequent 180 of rotation Phase II will be performed through conveyor 22 while Phase I is being performed through conveyor 23. The manner in which these results are obtained, and also the manner in which the detailed control features discussed above are obtained, will be. evident from consideration of Figure 11 in the light of the following discussion.

In starting the system into automatic operation for practice of Phase I through conveyor 22, the portion of conveyor 21 between its transverse center line and conveyor 23 may first be supplied with tobacco by means independent of the control system now to be described, and we will assume that this is the condition at the start of the automatic operation. We will also assume that the motors driving conveyors 21, 22 and 23 are timed to produce conveying movements of these conveyors between the transverse center of conveyor 21 and its respective ends, between the receiving ends of conveyors 22 and 23 and their blowers 24 and 42, and between successive blowers, each of which conveying movement occurs dur ing 15 of rotation of shaft 61 which drives the timing cams.

Referring to Figure 11 of the drawing, the automatic operation is started by closing start switch100, safe run switch 101 and the synchronous motor SMS switch 102. The closing of switch establishes a circuit from line 103, which we will regard as the supply line, to return line 104 through line 105, stop switch 106, line 107, UV relay 108 and lines 110 and 111, and the resulting energization of relay 108 closes the switch contacts which it controls. We will refer to the uppermost of these as UV-l, the next lower as UV-2 and the lowest as UV-3, and employ this same system of nomenclature in referring to the other relay-controlled switch contacts of the system. Since contacts UV-3 are in circuit with switch 102, current will now flow from supply line 103 through switch 100, line 105, switch UV-3, switch 102 and synchronous motor 60, thereby starting the rotation of the cam shaft 61. The first effect of rotation of shaft 61 from the 0 starting point illustrated will be to close switches 114 and 115 by the rotation of SAFC cam 116 and SOC cam 117, respectively. Switch 115 is in circuit with line 104 through line 118 and with line 103 through line 119, SOR relay 122, line 123, contacts UV-2, line 107, and switches 106 and 100 and line 105 to supply line. 103. Relay contacts SOR-1 and SOR2 will accordingly be closed by the closing of switch 115.

Each of the switches controlled by the cams on shaft 61 except the switches controlled by the SOC, CA5 and CB10 cams is electrically interconnected through lines 124 and 125, contacts UV-1 and line 126 with supply line 103, and the closing of switch 114 accordingly establishes a circuit through these connections and through line 127, SAFR relay 128, line 129 contacts SOR1 and line 111 to return line 104, energizing relay SAFR and closing switch 65 to start the movement of conveyor 21. After 15 of rotation of shaft 61, the leading end of this bed of tobacco will have been moved from its position at the transverse center of conveyor 21 to position in which it is ready to be received upon conveyor 22. At this point, the timing controls operate to start the forward movement of conveyor 22 and the master feed conveyor 20, to establish a continuing supply of tobacco upon conveyor 21 as it continues to move forwardly, and to convey tobacco discharged from its forward end in a continuing stream or bed forwardly on conveyor 22.

Upon completion of 15 of rotation of shaft 61, TFC cam 132 and CAC cam 133 operate to close switches 134 and 135. A circuit is thus established through switch 134, line 136, contacts SOR-2, line 137, switch 101, TFR relay 138, line 130, contacts SOR-1 and line 111 to return line 104, and through switch 135 through line 142,

7 CAR relay 143, lines 144 and 129, contacts SOR1 and line 111 to the return line. Relays TFR and CAR will thus be energized simultaneously tostart the forward movements of conveyors and 22, by closing of the respective switches 62 and 73 controlling their driving motors.

After 15 of further rotation of shaft 61, the forward end of the advancing bed of tobacco will be in line with the nozzle of blower 24, as illustrated in elevation in Figure 4 and in plan in Figure 5. Blower 24 is now started and continued in operation during the next 15 of rotation, i. e., until shaft 61 has rotated from its initial position. The circuit through which this blowing operation is established is controlled by cam CA-l 145 in closing its associated. switch146. This establishes a circuit through lines 147 and 148, switches SO1 149 and LS-l 152, the motor of blower BL1, which is the blower 24 of Figures l-lO, lines153, 144 and 129 contacts SOR1 and line 111 to return line 104. Blower 24 will therefore be operated as long as cam 145 retains switch 146 in closed position, except under the abnormal conditions discussed below for preventing this blower from operating when its associated hopper 26 already has a full supply of tobacco. Thus, in the normal course of events, the switch 146 will retain blower 24 in operation during 15 of rotation of shaft 61 and all of the tobacco fed forwardly at the advancing end of the bed upon conveyor 22 will be deflected into hopper 26 during this operation of the blower.

After the operation of blower 24 has stopped by reason of the fact that cam 145 opens its switch contact 146, the shaft61 will continue to rotate forwardly for 15 during continued forward movement of conveyors 20, 21 and 22. At the end of this time, shaft 61 will be at its position, and switch l54will be closed by rotation of cam 155 into its switch-closing position. This will establish a circuit through lines 156 and 157, switches SO-2 158 and LS?. 159, blower. BL-Z 27 and line 153 to the return connections discussed above forthe circuit through blower BL1 24. Cam CA2 will open its switch contact 154 after 15 of further rotation, i. e., at the position of shaft 61, thereby stopping blower 27 and the deflection of tobacco into hopper 32.

The leading end of the bed of tobacco on conveyor 22 will next move forwardly to the position of Figure 7, and blowers 28 and 29 will be operated in sequence, with a 15 interval between operations, by switches 162 and 163 controlled by earns 164- and 165, respectively, for closure during 15 of rotation of shaft 61, with intervals of time corresponding to 15 of rotation between the opening of each of these switches and the closing of the next succeeding switch, to permit the material to progress forwardly upon conveyor 22 between successive blowing operations.

After completion of the feed of equal increments of tobacco to the respective hoppers 26, 35, 36 and 37 as discussed above, and the stopping of the operation of blower 29, the tobacco will move forwardly without operation of any blower during 15 of further rotation of shaft 61, and it will then begin to spill over into discharge duct 38 and hopper 39 and continue to be fed to hopper 39 in this way during 15 of further rotation of shaft 61. At this time, shaft 61 will be at its 165 point, and the entire feeding system is now stopped, since Phase I has been completed.

From the discussion of SOC earn 117, it was seen that, by the operation of this cam the switch is closed and that this switch controls, through line 119 and relay 122, contacts SOR1 and SOR-2. It has also been seen that contact SOR-ll is a part of the return circuit for the relays 138 and 128 controlling the forward feed of all con-- veyors 20, 21 and 22. The normal effect of cam SOC 117 in opening switch 115 after of rotation of shaft 61 would accordingly be to stop the forward movement of these conveyors with the bed of tobacco at the position an interruption of the feeding operation is prevented, in.

normal operation of the system, by the fact that cam CA-S 166 closes its associated switch 167, thereby establishing a parallel circuit through SOR relay 122. This parallel circuit includes normally closed switches LS-S 168 and SO-S 169, whose function will be explained hereinafter.

Fromthe foregoing, it will be seen that in the normal operation of Phase I, SOR relay 122 will remain energized and its associated switch contacts closed during the first 135 of rotation of shaft 61 by closure of switch 115' by SOC cam 117, and that this condition will continue during 30 of additional rotation of shaft 61, through closure of switch 167 by CA5 cam 166. To accomplish this continued energization of the SOR relay and the conveyor feed, the cams are designed so that switch 167 is closed before switch 115 is opened. Cam 117 may, forexample, allow switch 115 to open when shaft 61reaches the 135 point, while cam CA-S retains switch 167 closed from 134 to switch 115 again at There is a time interval of 30 of rotation of timing shaft 61 between the end of Phase I and the beginning of Phase II and the beginning of Phase 11 during which conveyors 20 and 22 are idle, since cam switches 134.and 135 are allowed to open by their cams TFC and CAC during this time. 135 are again closed by their cams TFC 132 and CAC 133, for the feeding of conveyor 20 forwardly in the performance of Phase I of the process to machines B-l to B5 through conveyor 23' and thefeeding of conveyor 22 forwardlythrough 150 in performance of Phase II to .machines A-1 to-A5. Conveyor 21 is started in reverse when shaft 61 reaches 180; i. e., 15 in advance of the starting of conveyors 20 and 23, in order to move the bed of tobacco previously deposited and lying between its center and conveyor 22, toward conveyor 22. until it begins to spill over onto conveyor 23.

In the completion of the feeding steps of Phase II, from conveyor 22 to the A group of machines, the blowers BL14 are started up simultaneously with conveyor 22.

at 195. This is achieved through closure of switch 182 by CAA cam 183 completing a circuit through line 181, CAAR relay 184 and the connections through line 144 to return line 104. Energization of relay 184 closes switch group 79, and the parallel blower circuits controlled thereby. Simultaneously with the closing of switch 182 by CAA cam 183, switch 185 is closed by CAAC cam 186, thereby completing parallel circuits through contacts CAAR 1, 2, 3 and 4, lines 187, 188, 189 and 190 and the motors operating blowers 24, 27, 28 and 29, and causing the tobacco to be simultaneously blown into the supply hoppers 26, 35, 36 and 37 as illustrated in Figure 10, as it is fed forwardly.

Cams SARC, CB, CB-1, CB2, CB3, CB-4, CBC, CBBC and CB-IO perform exactly the same functions in control of relays SARR 191 and CBR 193, blower BL-6 42, blower BL'7 43, blower BL-S 44, blower BL-9 45, the simultaneous operation ofblowers BL69 in Phase II through energization of CBBR relay 194, and the maintenance of closed circuit through switch 195 after cam SOC again allows switch 115 to open at 315 in feed to the B group of machines, as do the corresponding cams SAFC, CAC, CA-1, CA-Z, CA-3, CA-4, CAA, CAAC and CA5 which control the conveyors and blowers associated with the feed to the A group. The only difference in these controls lies in the fact that the cams controlling the B group operations are timed to perform their corresponding functions exactly 180 after the corre-- sponding functions of group A. Thus, the wiring conalternation in the two groups during successive 180" intervals of each 360 of shaft rotation.

Cam SOC will operate to close After this interval, switches 134 and Each of the parallel circuits through the blower motors includes a switch responsive to the level of material in the hopper into which material is blown by that blower, these being designated LS-l, LS-2, etc. These are normally closed, and when all of them are in that condition, and the corresponding switches SO-l etc. are also closed, the apparatus will perform its complete operating cycle in delivering increments of tobacco sequentially into each hopper. When the tobacco has accumulated to a maximum desired level in a hopper associated with any blower, however, its LS switch will open, thus disabling that blower at the time it would normally operate. Thus, if LS-l switch 152 is opened by the level of tobacco in hopper 26 during Phase I at the time switch 146 is closed to operate BL-l blower 24, such operation will be pre vented, and the body of tobacco which would normally be deposited in hopper 25 will be deposited instead in hopper 39, and the same comment applies to any of hoppers 35-37 that may be skipped in this manner. If any of the blowers is similarly disabled 'in Phase II, the increment of tobacco which would normally be received in the associated hopper will be received by the next hopper down the line which requires any tobacco, and with which its associated blower is accordingly functioning.

If one of the machines should be shut down for repairs or other reason, it will ordinarily be desirable to discontinue feed to its associated hopper, and this may be done by manually opening its respective SO 1-9 switch such as SO-l switch 149 in the line of blower BL-l. The effect of this will be the same as that discussed above for opening of the corresponding LS switch.

It is desirable that the feed to hoppers 39 and 50 be interrupted at times, both because of the fact that these might otherwise be oversupplied in normal course of operation, and because of the fact that they receive somewhat of an oversupply because of occasional interruption of one or more of the blowers through the LS and SO switch controls discussed above. In order to correct this, there are provided in the branch circuit controlled by switch 167 and CA-S cam 166, a limit switch LS-5 168 and a shut-off switch SO5 169, and there are correspondingly provided, in the circuit controlled by the switch 195 and cam 196, a limit switch LS- 197 and shut-off switch 80-10 198. These switches are identical in their functioning to the LS and SO switches associated with the blowers, the limit switches being in every case associated with the corresponding hoppers to effect their control functions in case of an oversupply, and the shutoff switches being available to the operator to disable the feeding function in case the machine is shut down. The functions of switches 168 .and 197 in preventing an oversupply are, however, to disable the feeding system at the point when the leading end of the tobacco being fed would ordinarily proceed from the position of Figure 8 to the position of Figure 9. Thus, if switches in the circuits controlled by the cam-controlled switches 167 and 195 are open, feed cannot occur to either of hoppers 39 or 50 as the final step in performance of the operations of Phases I and II as discussed above. Cam SOC allows its associated switch 115 to open from 135 to 180 and from 315 to 360, but relay SOR is normally maintained energized between 135 and 165 and between 315 and 345 by the closure of switches 167 and 195 by their cams 166 and 196 for 31 intervals beginning at 134 and 314. Thus, when these branch circuits are opened by opening of switch 168 or 169 and switch 197 or 198, the feeding operations will be interrupted without feeding any tobacco through the last 30 of movement of conveyor 22 or 23, in either Phase I or Phase II. While an occasional increment of feed will be received by these hoppers even when these switches are open, as will be evident from an analysis of the system, the controls may be applied to prevent the end hoppers from becoming oversupplied. If it should be desired to prevent any tobacco whatever from reaching these hop- 10 pers, special conveyor or control features may be ap plied to cause recirculation to the supply source of to-' bacco which would otherwise be received at undesired times, or other special control or conveyor features may be adopted.

While the invention has been described above in relation to a preferred embodiment of the invention by way of example, persons skilled in the art will be aware that it may be modified or refined in various ways without departing from its basic principles. We therefore wish to have it understood that this invention is not to be limited in interpretation except by the scope of the following claims.

We claim:

1. In apparatus for feeding bulk material to a plurality of serially arranged spaced locations, the combination comprising conveying means having conveyor run portions movable through successive positions lying in feeding relationship to each of said locations, means for supplying material to said conveying means, blowers mounted laterally and above said conveying means and positioned above said respective locations to blow material from said conveying means into said locations, means for operating each of said blOWers through a predetermined time interval during advance of a body of said material forwardly upon said conveying means progressively into the range of each blower, timing means for controlling the performance of said supplying, material advancing and blowing steps in regularly timed repetitive cycles, and means associated with said supply locations and individually responsive to predetermined accumulation of material at said locations for interrupting the operations of said blowers at locations at which said material has accumulated to said predetermined extent, while continuing the operation of the remaining blowers during the continued regularly timed repetitive performance of remaining steps of the cycle.

2. An apparatus as defined claim 1 in which said timing means includes means for establishing a continuous supply of material on said conveying means opposite and rearwardly from each of said supply locations, and operating said blowers simultaneously during subsequent forward movement of said conveying means to carry the supply extending rearwardly from the respective blowers into the range thereof.

3. An apparatus as defined in claim 1, in which said timing means includes means for causing said conveying means to move forwardly with a continuous bed of material deposited thereon, and means for causing each of said blowers to operate through a predetermined time interval immediately following advance of the forward end of said bed of material within the range thereof.

4. An apparatus as defined in claim 3, in which said timing means includes further means operable, following delivery of a predetermined increment of material to each of said locations as therein defined, while further material is accumulated on said conveying means rear- Wardly of said locations, to cause said conveying means to move forwardly during a further predetermined time interval during simultaneous operation of all of said blowers to deposit a further increment of material at each of said locations.

5. In apparatus for feeding bulk material to a plurality of groups of serially arranged spaced locations, the combination comprising means to feed material to the locations of one of said groups comprising conveying means having conveyor run portions movable through successive positions lying in feeding relationship to each of said locations, means for supplying material to said conveying means, blowers mounted laterally and above said conveying means'and positioned above said respective locations to blow material from said conveying means into said locations, means for operating each of said blowers through a predetermined time interval during advance of a body of said material forwardly upon said conveying means progressively into the range of I each blower, timing means, for controlling, the performance of predetermined accumulation of materialat said locations for interruptingthe operations of said-blowers at locations at which saidmaterial has accumulated to said prede termined extent, while continuing the operation of the remaining-blowers during the continued regularly timed repetitive performance of remaining steps of the cycle.

6.,Inapparatus for feeding bulk materialto a plurality of serially arranged spaced locations, the combination comprising conveying means having conveyor run portions movable. through successive: positions lying in feeding relationship to each of said'locations, means for supplying material to said conveying,- means, blowers mounted laterally and above saidconveying means and positionedabove saidrespective locations to blow material from said conveying means into said locations, means for operating each-of said blowers through av predetermined time interval during advance of a body of said material forwardly upon said conveying means progressively into the range of each blower, timing means for controlling the performanceof said supplying; material advancing and blowing. steps inregularly timed repetitive cycles, and

me'ans'associated'with said supply locations and individually responsive to predetermined accumulation of material atsaidlocations for interrupting the operations of said blowers-at locations at which said material has accumulated to said'predeterm'ined extent, While continuing the operationofthe remaining blowers duringthe continued regularlytimed-repetitive performance of remaining. steps of the cycle, said conveying means includinga conveyor runv portion having its delivery end overlying a further supply location to deposit-increments of material therein bygravityin-time sequential relation to the deposit there-' References Cited'inthe file of thistpatent UNITED STATES PATENTS 418,042 Mitchell Dec. 24, 1889 2,140,128 Craggs Dec. 13, 1938 2,195,407 Craggs Apr. 2,1940 2,537,uu5 Brown et al. Jan. 9, 1951

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