Title:
BAG PACKER WITH HORIZONTAL TRANSFER
United States Patent 3641735


Abstract:
Apparatus for packing flexible bags into cases, the apparatus elevating the bags, dividing them into a plurality of channels, delivering them to a hopper having an accumulator chamber, the bags being dropped into the accumulator chamber one layer at a time, and when a case load is accumulated all bags being transferred into the case.



Inventors:
Daily, William C. (Covington, KY)
Welzel, Fred H. (Covington, KY)
Application Number:
05/004378
Publication Date:
02/15/1972
Filing Date:
01/20/1970
Assignee:
R.A. JONES & CO. INC.
Primary Class:
Other Classes:
53/540, 414/790.3, 414/790.6, 414/790.8, 414/794.2
International Classes:
B65B5/06; B65B35/50; (IPC1-7): B65B35/50; B65B5/06
Field of Search:
53/159,164,244,247 214
View Patent Images:
US Patent References:
3512336APPARATUS FOR PLACING FLEXIBLE PACKAGES IN SHIPPING CONTAINERS1970-05-19Rosecrans
3205794Shingle stacking and squaring1965-09-14Califano et al.
3126105N/A1964-03-24Marguet
2961086Apparatus for handling biscuits and the like1960-11-22Edis
2404882Article handling apparatus1946-07-30Monaco
1299198N/A1919-04-01Low et al.



Primary Examiner:
Custer Jr., Granville Y.
Assistant Examiner:
Spruill, Robert L.
Parent Case Data:


This is a continuation-in-part of our copending application Ser. No. 808,831, filed Mar. 20, 1969, now abandoned.
Claims:
We claim

1. A bag-packing machine comprising:

2. A bag-packing machine according to claim 1 wherein the means for delivering bags onto said upper trap comprise,

3. A bag-cartoning machine according to claim 1 in which each said upper and lower traps comprises:

4. A bag-packing machine according to claim 1 in which said hopper is formed by longitudinal vertical adjustable walls and divider means, and adjustable transverse walls.

5. A bag-packing machine according to claim 5 in which said transverse walls are disposed between said longitudinal walls and divider means and have side edges spaced therefrom to permit transverse adjustment with respect to said longitudinal walls and divider means.

6. A bag-packing machine according to claim 1 further comprising:

7. A bag-packing machine comprising:

8. A bag-packing machine according to claim 7 in which said delivering means include channelizing means to divert bags laterally to positions aligned with respective compartments.

9. Apparatus according to claim 2 further comprising:

10. Apparatus according to claim 2 in which the peripheral speed of said wheel is substantially greater than the peripheral speed of said belt.

11. Apparatus according to claim 10 in which said belt is impregnated with a low-friction material.

12. Apparatus according to claim 10 in which said belt has a lower coefficient of friction than said wheel.

13. Apparatus according to claim 11 in which said belt is impregnated with Teflon.

Description:
This invention relates to a bag-casing machine, and more particularly the invention is directed to a machine for automatically packing small flexible bags which are filled with particulate goods or goods of irregular shapes.

In the past, filled flexible bags have been packed into cases by hand. The flexible nature of the bags as contrasted to cartons, cans and the like has prevented the bags from being susceptible to handling by apparatus which is in common use for packing more rigid articles. Specifically, the problem has been one of maintaining control over the flexible bag as it is conveyed from the filling station to the casing station and continuing the control over the bag as it is deposited into a case so as to assure its assuming the desired orientation.

Rosecrans in U.S. Pat. application Ser. No. 663,573 filed Aug. 28, 1967 has described a bag packer which is addressed to the same problem of controlling a flexible bag from filling to casing as is the present invention. The Rosecrans apparatus includes, serially, a conveyor for the filled bags, an elevator, a channelizer for diverting a single file of bags into two or more files of bags, a conveyor for removing the bags from the channelizer, a gravity chute for conveying the bags from the conveyor to loading pockets, the bags being discharged from the loading pockets into a case.

The objective of the present invention is to improve upon the Rosecrans structure in several areas, thereby providing a greater control over the bags, particularly including the control of the bags as they are deposited into a case.

A particularly important area of control involves a hopper mechanism from which bags are deposited into cases for it is in the deposit of the bags into cases that the greatest problems arise. Assume, for example, that a case requires four layers of bags. The lowermost bag must be dropped a distance greater than the combined thickness of the four layers of bags. In dropping this distance, it has been found that the most difficult-to-handle bags will not drop completely flat, but will first hit the bottom of the case and thereafter crumple. The difficult-to-handle bags are those which are filled with particulate material, such as peanuts and frozen peas, and handle like a bean bag.

Further, if the bags are dropped one layer at a time into a case, after a case has been filled, the flow of bags must be stopped until the filled case is removed and an empty case brought into place.

The control of the deposit of the bags into the case is attained in the present invention by providing a hopper having an upper set of trap doors for receiving a single layer of bags and a lower set of trap doors upon which a full case load of bags can be accumulated. It has been found that whereas a single bag dropping the depth of a case may become disoriented, the cooperating action of a stack of bags dropping the depth of a case will maintain all bags of the stack in a flat orientation. Further, the time interval during which bags are accumulated in the hopper permits an operator to remove a filled case and bring an empty case into position below the hopper.

When the bags are dropped directly into a case from the lower set of trap doors, the bags will lie flat in the case. Some products, however, are most efficiently or effectively packed by placing the bags in the case on their side edges or on their ends. It is an objective of the present invention to accommodate this type of packing by providing apparatus below the lower set of trap doors for receiving an accumulated case load of bags in flat condition and thrusting that case load of bags transversely into a case which is supported on its side. When the case is turned so as to rest on its bottom wall, the bags will be supported in the case on their edges. If the apparatus is oriented to move the bags laterally with respect to their long dimension, then the bags when packed, will rest upon their side edges. On the other hand, if the bags are thrust into the case in a longitudinal direction, the bags will rest upon their end edges when the case is turned with its open side facing upwardly.

Another objective of the invention has been to provide means for delivering bags in a flat orientation to the upper trap doors of the hopper. The means include an arcuate chute having a vertical portion which receives the bags and a horizontal portion which discharges the bags onto the upper trap, and a friction wheel which engages the bags and drives them at an appropriate speed down the chute. The positive driving action of the friction wheel provides assurance that the bags will develop the speed required to slide to a proper position on the trap regardless of variations in the frictional characteristics of the bag surface as might be created by varying bag materials, printing inks, temperature conditions and the like.

Another objective of the invention has been to provide a check and release mechanism by which a row of two or more bags is captured above the chute. The mechanism provides for the release of the bags at a preselected time while checking the next adjacent row of incoming bags so that only one row of bags is released at a time. Associated with the check and release mechanism is a low friction conveyor belt which runs continuously to urge the bags toward the chute. In the preferred form of the invention, the belt has been impregnated with a low friction material, such as Teflon, and is particularly useful in the handling of especially floppy bags to avoid their bunching up in the check and release mechanism.

A further objective of the invention has been to provide, as an elevator, a double belt endless conveyor wherein the pulleys for one of the belts are mounted on a parallelogram linkage which can be pivoted with respect to the other belt to vary the spacing between the belts. Preferably, the parallelogram linkage is spring urged to close the spacing so that automatic compensation for bags of varying sizes is achieved.

Still another objective of the invention has been to provide case shifting mechanism associated with the hopper. The case-shifting mechanism is particularly adapted for use with cases which have been shipped flat from a converter. When opened and placed on the mechanism, the cases can be thrust under the hopper where they are releasably locked in alignment with the hopper while driving a filled case out from under the hopper. During this movement, the case bottom flaps are plowed to a closed condition and the case top flaps are held by guides in an open position as required for depositing the bags into the case.

These and other objectives of the invention will become more readily apparent from the following detailed description taken in conjunction with the accompanying drawings in which:

FIG. 1 is a diagrammatic side elevational view of the bag packing apparatus of the invention;

FIG. 2 is a top plan view taken in the direction of lines 2--2 of FIG. 1 and showing the channelizer mechanism;

FIG. 3 is a top plan view taken along lines 3--3 of FIG. 1 and showing the check release mechanism;

FIG. 4 is a cross-sectional view taken along lines 4--4 of FIG. 3;

FIG. 5 is a diagrammatic side elevational view, partly in section, of the hopper mechanism;

FIGS. 6 and 7 are views similar to FIG. 5 illustrating succeeding stages of operation;

FIG. 8 is a diagrammatic front elevational view of the hopper and case-loading mechanism, taken along lines 8--8 of FIG. 5;

FIG. 9 is a perspective view of the cam timer which programs the sequence of bag-loading operations;

FIG. 10 is a top plan view of the case-loading apparatus, taken along lines 10--10 of FIG. 8;

FIG. 11 is a top plan view, partly in section, of the case-loading mechanism illustrating an early stage of the loading operation;

FIGS. 12 and 13 are views similar to that of FIG. 11 illustrating succeeding stages in the case-loading operation;

FIG. 14 is a cross-sectional view taken along lines 14--14 of FIG. 10;

FIG. 15 is a cross-sectional view taken along lines 15--15 of FIG. 11;

FIG. 16 is a diagrammatic side elevational view illustrating the transverse packing of bags in a longitudinal direction; and

FIG. 17 is a diagrammatic front elevational view illustrating the transverse packing of bags in a lateral direction.

GENERAL ORGANIZATION AND OPERATION

Referring to FIG. 1 of the drawings, the bag-packing apparatus indicated at 20 includes a horizontal endless conveyor 21 which receives bags 19 from a bag filler indicated generally at 22. The bags 19 are conveyed by the belt 21, single file, to an elevator 23. The bags are discharged at 24 from the elevator to a channelizer 25 wherein the bags are diverted, single file, to two or more files. In the illustrated embodiment of the invention, three files are shown.

The bags are delivered at 26 from the channelizer to a three-belt conveyor 27. Overlying the three-belt conveyor 27 is a check and release mechanism 28 which receives and holds two aligned rows of incoming bags as shown in FIG. 3. At a preselected time, the check and release mechanism releases the leading row of bags while holding the next adjacent row of bags momentarily. The conveyor 27 conveys the row of three bags to a nip 29 formed between a friction wheel 30 associated with each belt 27, the nip 29 and wheel 30 overlying an arcuate chute 31. The bags are driven by the friction wheel downwardly onto the chute 31 from which they slide freely to an upper trap 32 associated with a hopper 33. Immediately below the upper trap 32 is an accumulator chamber 34 having a bottom wall formed by a lower trap 35. A horizontal support 36 for a case 37 is located immediately below the hopper 33.

The single layer of bags delivered to the upper trap 32 is released to fall into the accumulator chamber 34. When the desired number of layers (for example four) is reached, the lower trap 35 is opened to release all of the bags into the case 37. Thereafter the filled case is removed and an empty case brought into its place.

Elevator Mechanism

The elevating mechanism includes a lower endless belt 40 having an upper reach 41, one portion 42 of which extends in an upper direction and another portion 43 of which extends horizontally. A second belt 44 passes about upper and lower pulleys 45 and 46 respectively. The belt has a lower reach 47 which lies parallel to and spaced from the portion 42 of the upper reach of belt 40. An elevator is provided between the upper reach of the lower belt and the lower reach of the upper belt between which bags 19 pass. Preferably, longitudinally spaced leaf springs 48 are associated with one or both of the belts to urge the belts toward each other. The leaf springs 48 are particularly useful where bags of indeterminate sizes are conveyed up the elevator in that they prevent the possibility of a large bag separating the two opposed reaches to such an extent that succeeding bags cannot be frictionally engaged between the reaches and carried up the elevator.

The pulleys 45 are rotatably mounted on a bar 49 which is supported on links 50 and 51. The links are pivotally mounted at their upper ends to the bar 49, and their lower ends are pivotally mounted to the frame of the machine indicated diagrammatically at 52. A spring 53, connected at one end to the frame 52 and at the other end to link 50, is under tension and urges the upper belt toward the lower belt. Through the parallelogram linkage and the spring 53, space between the two belts is automatically variable to accommodate bags of varying sizes.

The Channelizer

The horizontal portion 43 of the lower elevator belt 40 discharges bags in single file onto the channelizer 25. The channelizer is a known device for diverting articles from a single file to plural files. A channelizer useful with the present invention is manufactured by Illumitronic Engineering, Sunnyvale, California, Model No. CH4. It includes an endless conveyor of transverse rods 60 which carry elongated block 61 slidable on the rods. A diverting mechanism located underneath the upper flight of the conveyor formed by the rods guides a preselected group of blocks 61 in a predetermined direction so as to form a pad 62 suitable for carrying an individual bag 19 in the predetermined direction. The diverter mechanism shifts the blocks 61 to form pads moveable selectively in one of three primary directions at intervals determined by the appearance of a bag 19 on the discharge end of the elevator 23 passing through a beam 63 from a lamp 64 which interrupts its impingement on a photoelectric cell 65. In the event of a malfunction of the apparatus, the channelizer can be adjusted to convey all bags on a fourth path indicated at 67 which drops the bags into a container 68 until the fault is cleared or the apparatus is shut down. The channelizer discharges at its downstream end 69 onto the three belt conveyor 27.

Conveyor Apparatus Between Channelizer and Hopper

The conveyor 27 has three belts 75, each of which is preferably impregnated with an antifriction material such as Teflon. The belts convey the bags 19 through the check and release structure to the chute 31. During this conveyance, the bags are confined to their respective belts by longitudinal guides 76 forming outer walls for the conveyor 17 as well as two dividers between the three belts. As illustrated in FIGS. 3 and 4, each check and release mechanism 28 overlying each respective belt includes an elongated arm 77 which is mounted on a bar 78, the bar being rotatably mounted on the guides 76 to be able to pivot the arm 77 between its two operative positions described below. The bar 78 is rotated by a double acting piston cylinder 79 attached to an arm 80 fixed to the bar 78. The actuation of the piston cylinder is determined by the timer shown in FIG. 9 to be described below.

The check and release arm 77 has a stop 81 fixed to its downstream end, the stop 81 being adapted to move into the path of a leading bag 19 to block it momentarily from passing on to the chute 31. The upstream end of the arm 77 provides means for checking momentarily the movement of the next adjacent bag 19 when the leading bag is released. The upstream end of the arm is formed by a spring 82 and a foot 83 attached to the end of the spring. The foot 83 engages a secondary arm 84 pivoted at one end to a rod 85 which is mounted on a bar 86, the bar being secured to the guides 76. The secondary arm 84 preferably has a curved undersurface, as indicated at 87, for it provides direct contact with the bags, and the curved undersurface avoids inflicting damage on the thin bag walls.

As viewed in FIG. 4, clockwise rotation of the arm 77 brings the stop into the path of incoming bags while raising the foot 83 to release the flow of incoming bags. The spacing between the stop on the one hand and the check means formed by the foot 83 and the arm 84 on the other hand is sufficient to allow the passage of one bag. Counterclockwise movement of the arm 77 brings the foot 83 into engagement with the secondary arm 84, thereby holding or checking the bag underneath it while releasing the leading bag for movement toward the chute 31, it being understood that the belts 75 run continuously. It should be noted further that a variation in the length of the bags with which the check and release will cooperate is permitted simply by adjusting the spacing between the bar 78 which carries the arm 77 and the rod 85 which carries the secondary arm 84.

Upstream of the check and release is a limit switch 1LS which is closed by the presence of a bag 19 underneath it. In the absence of a bag underneath it, the operation of a cycle motor which programs the discharge of bags to the hopper will cease, thereby providing assurance that there will be a sufficient supply of bags for full loading of the cases before the check and release operates. Only one limit switch is shown, but it should be understood that three limit switches, one for each belt, can be provided.

The bags are discharged by the check and release mechanism 28 from the conveyor 27 onto the chute 31. The chute, as shown in FIG. 1, is arcuate, the upper portion 90 projecting generally vertically and the lower portion 91 projecting generally horizontally. The chute has side walls 92 and dividers 93 which form three channels 94 to guide the bags in proper alignment onto the upper trap 32 overlying the hopper. The upper surface of the chute is preferably lined with nylon or like low friction material.

Immediately above the chute are the wheels 30, one wheel corresponding to each chute channel 94. The wheels are fixed to a shaft 95 journaled in the walls and dividers 92 and 93 and being driven by a chain passing over a sprocket 96. Each wheel 30 forms the nip 29 with respect to its respective conveyor belt 75 as the conveyor belt passes around its pulley. The function of each wheel is to frictionally engage a bag released from the end of belt 75 and to drive that bag through the nip downwardly onto the upper portion 90 of the chute 31. To provide proper engagement of the wheel 30 with the bag, the surface of the wheel is preferably formed of rubber or like resilient material and has a series of transverse teeth forming its periphery. The wheel 30 is preferably driven at about twice the speed of the belt 75, although the speed of the wheel will be dependent upon the particular conditions and specific structural relationships involved. The importance of the high speed of the wheel is that it imparts to the bag a sufficient force to cause it to make a full traverse of the chute 31 and to arrive in a flat condition on the upper trap 32. Too great a speed might cause the bag to bunch up at a stop associated with the trap (to be described below), and insufficient speed would prevent the bag from covering the full distance.

The Hopper

The hopper 33 is best shown in FIGS. 5-8 and includes longitudinally extending vertical outside walls 100 and parallel divider walls 101, all adjustably mounted on transverse rods 102. The hopper also includes narrow front and rear transverse walls 103 whose edges are normally spaced from the walls 100 and dividers 101 to permit adjustment of the latter without interference from the transverse walls. The transverse walls are mounted on threaded rods 104 which are in turn adjustably secured to frame structure indicated at 105 to permit their adjustment. The longitudinal walls and dividers together with the transverse walls provide adjustable compartments 106 adapted to receive a stack of bags, and, as indicated, the size of the individual compartments can be varied to accommodate bags of varying sizes. The individual compartments 106 collectively form the accumulator chamber 34 in which a full case load of bags is accumulated before being dropped into the case 37. The upper trap 32 is located immediately above the accumulator chamber 34. (The trap is shown spaced somewhat from the accumulator chamber, but it is to be understood that it should be as close as is structurally possible in order to minimize the distance of the bag drop into the bottom of the accumulator chamber.) The trap includes a pair of guillotine doors 110 which are mounted for horizontal sliding movement and which are connected through a bellcrank lever 111 to a piston and cylinder 112. Operation of the piston and cylinder causes the bellcrank lever to pivot and, through slotted connections 113 to the guillotine doors, to open the guillotine doors 110 permitting a bag to fall through (FIG. 6). This action is preferably quite rapid so that the bag does not begin to sag as the doors are opened.

Similarly, at the lower side of the accumulator chamber 34 and forming a bottom therefor is the trap 35 formed by guillotine doors 114 which are actuated similar to guillotine doors 110 through bellcrank lever 115 and piston and cylinder 116. The actuation of the piston and cylinder 116 causes the bellcrank lever 115 to pivot, thereby sliding the guillotine doors 114 horizontally to permit the accumulated stack of bags to drop simultaneously from their respective compartments 106 (FIG. 7).

Immediately above the upper trap 32 is an adjustable stop 117 mounted on a rod 118 which is adjustably secured to the apparatus indicated generally at 105. The stop 117 positions the bags longitudinally with respect to the compartments 106.

Case Transfer Mechanism

The case transfer mechanism is illustrated in FIGS. 10-15, although reference should be made to FIG. 8 to understand the overall orientation of the mechanism with respect to the hopper structure. As shown in FIG. 8, the transfer mechanism includes an elongated flat plate 130 which forms a saddle to support an empty case 37 with bottom side flaps 131 extending downwardly along the sides of the saddle 130 and with bottom end flaps 132 lying flat upon the saddle 130. This structure permits the operator to open and make a preliminary formation of the case from the flat state in which it is received from the converter.

Below the saddle 130 are a pair of angulated plows 133 (FIGS. 14 and 15) which are engaged by the bottom side flaps 131 as the case is thrust toward its loading position under the hopper. As illustrated in FIGS. 14 and 15, the plows fold the side flaps upwardly along the bottom of the case to complete the formation of the bottom of the case.

Overlying the saddle 130 and extending under the hopper 33 are a wide flap guide 134 and a narrow flap guide 135. The narrow flap guide 135 is engaged by the downstream flap 137. The wide flap guide 134 is engaged by the top end flaps 136 and the top upstream side flap 137 of the case 37 to hold those flaps in an open condition until the case is brought fully under the hopper. It will be observed with particular reference to FIGS. 12-15 that the saddle 130 is offset with respect to the center of the hopper 33. This offset relation enables the forward top end flap of the case to underlie the flap guide 134 during its initial movement in a position under the hopper. If the hopper and saddle 130 are aligned, it would not be conveniently possible to use a stationary guide to hold the end flap in open condition, for such a stationary guide would obstruct the path of the bags from the hopper into the case.

The support 36 for the cases underneath the hopper, and adjacent the saddle 130, is formed by rollers 140 which provide convenient antifriction means for rolling a loaded case out from under the hopper.

At the downstream side of the structure, an elongated case side guide 141 is provided against which the case will be lodged to position it underneath the hopper. A roller 142 is mounted on the end of the guide 141 to serve as a detent for the forward end of the case. A spring loaded stop 143 is mounted on the side guide at the rearward end of the case when it is under the hopper to block inadvertent rearward movement of the case when its pusher, to be described below, is returned to its starting position.

A pivoted side guide 145 is at the opposite side of the hopper, the pivoted side guide being mounted on brackets 146 which are pivoted on a rod 147 and urged by a spring 148 in a counterclockwise direction as viewed in FIGS. 14 and 15. The pivoted side guide 145 has an angulated rearward end 150 which provides a flaring entrance for the case as it is thrust into position under the hopper (See FIG. 11), and a stop finger 149 at its forward end which properly positions a case 37 beneath the hopper 33. It will be recalled that the saddle 130, which initially supports the case is offset with respect to the center of the hopper. As the case is thrust into position under the hopper, the case engages the angulated member 150 camming the side guide 145 away from the side guide 141. However, after the case is under the hopper and has passed beyond the saddle 130, the spring 148 returns the pivoted side guide and thrusts the case toward the fixed side guide 141, thus centering the case under the hopper. A lever 151 is attached to the pivoted side guide to permit manual assistance in pivoting the side guide to one side or the other.

A limit switch 4LS is located on the fixed guide 141 adjacent the roller 142 to detect the presence of a case centered under the hopper. The function of the limit switch will become more apparent in connection with the description of the timing operation.

A pusher 155 is pivotally connected at 166 to a block 167 slidably mounted on rods 168 forming ways running parallel to the fixed side guide 141. The pusher has a handle 169 by which the operator pivots the pusher, moving it to-and-fro to effect the transfer of the cases. The pusher has a rearward arm 170 extending transversely across the saddle 130 and a forward arm 171 extending transversely across the saddle 130. The arm 170 is to engage the rear side of a case to push it into position under the hopper. The arm 171 is to engage the rear side of a filled case and push it out from under the hopper as the empty incoming case is thrust into position. A rearwardly facing edge 172 of the arm 171 is angulated so that as the pusher is moved to the right, as viewed in FIGS. 10-12, it will be cammed by engagement with the incoming case to pivot counterclockwise to clear it for movement to its starting position. As indicated above, the spring biased stop 143 prevents a return of that case even when a return component of force is imparted to it by the return of the pusher.

In the operation of the case transfer mechanism, let it be assumed that a filled case is in the position shown in FIG. 10. An empty case in flat condition is opened and placed on the saddle 130 with the bottom side flaps extending downwardly alongside the saddle 130. The operator begins to thrust the empty case into position under the hopper. During the initial movement, the forward arm 171 of the pusher engages the filled case and thus removes the finger 149 from its blocking position with the filled case. The inward movement of the empty case engages the pivoted side guide and begins to swing it away from the fixed guide. In the meantime, the upper side flaps 137 have moved under the respective flap guides, and the forward end flap 136 moves under the wide guide 134. Underneath the case, the depending side flaps 131 have engaged the plows 133 to begin the folding of those flaps underneath the case. As the thrust of the pusher continues, the filled case rolls over its roller detent 142 (FIG. 12) to free it for continued rolling on the support rollers 140 and out of the apparatus. The incoming case continues to move in an offset path, as indicated by FIG. 12, until it begins to clear the tapered end of the saddle 130. As it clears the end of the saddle 130, the spring pressure of the pivoted side guide forces the case into a precise longitudinal alignment underneath the hopper, and the finger 149 stops forward movement of the case so that it is in a proper position for loading. It is held in this position between the fixed and pivoted side guides, the roller and the finger at the forward end, and the spring detent at the rearward end as shown in FIG. 13. The operator then returns the pusher to the starting position.

It should be understood that the apparatus described above can be replaced by automatic case opening and transfer apparatus without affecting the overall operation of the invention.

The Timing Cams

The loading of the bags into the case is programmed by the timing cams shown in FIG. 9. Cams C2, C5-C14 are mounted on a shaft 175, which is driven by a motor 176, which is connected through a timer 177 and a limit switch 1LS to a source of voltage. Each cam is associated with a respective limit switch 2LS, 5LS-14LS. 2LS completes a holding circuit to the motor 176, opening the circuit to the motor only when its switch arm drops into a dip 202 on the cam C2. There are four dips 202 on the cam C2 90° apart, each dip corresponding generally to the drop of one bag.

The limit switch 5LS is connected in parallel with the limit switch 4LS in series with timer 177 contact which is parallel with 2LS to the timer motor 176 and to a final drop solenoid actuated valve which operates the piston and cylinder 116 through 14LS associated with the lower trap 35. The limit switches 6LS-9LS are connected to the check and release to operate it when one of their switch arms drops into respective dips 206-209. The limit switches 10LS-14LS are connected to a solenoid operated valve, not shown, which operates the piston and cylinder 112 to open the upper trap 32 when one of their arms drops into the respective dips 210-214 in their respective cams C10-C-14.

In the operation of the timing mechanism, the presence of a full supply of bags at the check and release position operates switch 1LS.

Operation

In the operation of the invention, the bags are filled and discharged on the conveyor 21 in single file order and carried to the elevator 23. The elevator carries the bags 19 upwardly and discharges them onto the channelizer 25. As each bag interrupts the photoelectric cell circuit, the channelizer diverts the bags sequentially to the three conveyors 75. The conveyors 75 carry the bags into engagement with the stops 81 of the respective check and release mechanisms until there is a backup of bags sufficient to operate the switch 1LS.

The operation of the switch 1LS energizes the timer 177. After a 3-second delay timer 177 energizes timer motor 176. The timer provides assurance of sufficient bags at the check and release. The energization of motor 176 causes rotation of shaft 175. The shaft 175 carries the cam C2 a distance sufficient to permit the arm of limit switch 2LS to ride out of its dip, thereby completing a holding circuit to the timer motor, which holding circuit assures the continuation of the operation through 90° of rotation, or until the next dip is encountered. Within a few degrees of rotation of shaft 175, limit switch 6LS is operated to operate the check and release the first time. That involves closing a circuit which operates the piston and cylinder 79 to rotate the bar 78 counterclockwise, as viewed in FIG. 4. Thus, the leading bags 19 are permitted to pass through the chute while the next adjacent bags are checked. The three bags thus released by their respective check and release mechanisms are thrust by the wheel 30 downwardly onto the chute, whereafter they slide freely into a position on upper trap 32 overlying the hopper.

Limit switch 10LS is then closed to operate the piston and cylinder 112 for the upper trap 32 to drop the first layer of three bags into their respective compartments 106 in the accumulator chamber 34.

The foregoing sequence of operations is continued through the operations of limit switches 7LS for the check and release and 11LS for the second stage drop; 8LS for the check and release and 12LS for the third stage drop; 9LS for the check and release and 13LS for the fourth stage drop.

Meanwhile, a case has been moved under the hopper to operate limit switch 4LS. If no case is present, limit switch 4LS will interrupt the circuit to the timer motor 176 to stop it from running and will interrupt a circuit to the solenoid-operated valve which actuates the piston and cylinder 116 to prevent the opening of the lower trap. The normal operation, however, is for limit switch 4LS to be closed. Limit switch 5LS, in parallel with limit switch 4LS, has its dip 205 aligned with that of limit switch 14LS and will prevent the full drop of the bags into the case unless the limit switch 4LS is closed.

Immediately following the fourth stage drop which fills the accumulator chamber 34, 14LS is operated to close a circuit to the solenoid-operated valve which controls the piston and cylinder 116 to open the lower trap 35, dropping the accumulated bags into the case. Thus, a case is filled.

The operator, operating the case transfer as described above, thrusts the filled case out and brings the empty case in. While the operator is making this adjustment, the bag packing apparatus continues to run, loading bags into the accumulator chamber. This preliminary loading of bags into the accumulator chamber provides sufficient time for the operator to complete removal of the full case and the introduction of the empty case.

In the foregoing description of the apparatus and its operation, the bags have been dropped from the lower trap doors of the hopper 33, directly into a case so as to lie flat in the case. In the alternative embodiments of FIGS. 16 and 17, the accumulated bags are dropped from the hopper onto a platform and are then thrust transversely into a case laying on its side so that the bags in their final orientation will be on their side edges or end edges.

Referring to FIG. 16, the hopper apparatus above and including the lower trap doors 35 is identical to that previously described. Below the trap doors 35 is a platform 180 onto which an accumulated load of bags 19 will drop. The platform 180 may be a part of a receiving chamber having vertical walls which will maintain the bags in an orderly arrangement prior to introduction into a case.

A support 181 is located in front of the platform 180 and preferably forms part of automatic case opening and transferring apparatus which brings a case 182 into a position in front of the platform 180 with the case flaps 184 opened so that the case is adapted to receive the bags 19. On the opposite side of the platform 180 is a ram 186 operated by a piston and cylinder combination 187. The ram has a plate 188 engageable with a stack of bags 19 to thrust the bags in a longitudinal direction into the case 182.

In the operation of FIG. 16 bags are loaded into the hopper 33 in the manner described above until a full case load is received. Thereafter, the lower trap doors are opened to permit the accumulated case load of bags to drop onto the platform 180. During the time that the hopper is being loaded, a case 182 has been brought into position on the support 181. As soon as the bags are in position on the platform and the case in position on the support, the ram 186 is actuated to thrust the bags into the case.

It will be observed that after the case 182 is loaded and is set on its bottom wall indicated at 189, the bags will stand on their end edges 190.

Apparatus similar to that of FIG. 16 is shown in FIG. 17. The principal difference between the two apparatus is that in FIG. 16 the bags are thrust into a case in a generally longitudinal or machine direction and will stand on their end edges when the case is in upright position. In FIG. 17, on the other hand, the bags are thrust laterally into a case and will stand on their side edges when the case is in upright position. As shown in FIG. 17, a bag-receiving platform 191 is located immediately below the trap doors 35 to receive a load of bags from the hopper 33. Again, it is preferred that the platform have sidewalls to maintain the bags in an orderly arrangement after they have been dropped onto the platform. At one side of the platform is a case support 192 forming part of case opening and transferring mechanism used to bring a case in opened condition alongside the platform 191. As mentioned above in the description of FIG. 16, the case is brought in position on its side 197 and its bottom 198 in a vertical attitude. On the opposite side from the case is a ram 193 operated by a piston and cylinder combination 194 and having a plate 195 engageable with the stack of accumulated bags.

In the operation of the apparatus of FIG. 17, when a case load of bags has accumulated in the hopper 33, the trap doors 35 open, dropping the accumulated bags onto the platform 191. When a case is in position and when the bags are in position, the piston and cylinder combination is operated to drive the ram toward the case thereby thrusting the stack of bags from the platform into the case.

When the case has been loaded and is set upright, it will be observed that the bags will be stacked on their side edges.