US3410046A

US3410046A - Case filling and stacking machine

Info

Publication number: US3410046A
Application number: US415667A
Authority: US
Inventors: John A Johnson
Original assignee: CEDAR HILL FARMS Inc
Current assignee: CEDAR HILL FARMS Inc
Priority date: 1964-12-03
Filing date: 1964-12-03
Publication date: 1968-11-12
Anticipated expiration: 1985-11-12

Description

Nov. 12, 1968 J. A. JOHNSQN 3,410,045

CASE FILLING AND STACKING MACHINE 7 Filed Dec. 5, 1 964 4 Sheets-Sheet 1 INVENTOR Ja/m l2? Johnson W AT'TY- Nov. 12, 1968 Filed Dec. 3, 1964 J. A. JOHNSON CASE FILLING AND STACKING MACHINE 4 Sheets-Sheet 2 INVENTOR dolm 17. Johnson Nov. 12, 1968 .1. A. JOHNSON CASE FILLING AND STACKING MACHINE 4 Sheets-Sheet 5 Filed Dec.

INVENTOR Nov. 12, 1968 J. A. JOHNSON CASE FILLING AND STACKING MACHINE Filed Dec. 3, 1964 4 Sheets-Sheet L INVENTOR swa (la/2n Halo/"wan United States Patent 3,410,046 CASE FILLING AND STACKING MACHINE John A. Johnson, Milford, Ohio, assignor to Cedar Hill Farms, Inc., Cincinnati, Ohio, a corporation of Ohio Filed Dec. 3, 1964, Ser. No. 415,667 15 Claims. (53-61) ABSTRACT OF THE DISCLOSURE Apparatus adapted to assemble gabled cartons containing milk, or the like, in patterns, depositing the cartons in patterns into shipping cases, and then vertically stacking the filled shipping cases. A counter-balancing means between the carton pattern lowering means and the stacker raising filled cases into stacked position. Conveyor located switches operated by movements of cases on a conveyor controlling the casing and stacking mechamsms.

The present invention relates to improvements in machines for filling cases with containers, such as milk cartons, and is particularly directed to simplified and coordinated mechanisms adapted to load milk cartons into cases, stack the filled cases and then deliver the stacked cases to a loading or a storage station.

An object of this invention is to provide a novel and efiicient carton caser and stacker apparatus that transfers the potential energy available at the case filling station to the case stacking station, whereby, in operation, the descending mass of the carton pattern being loaded into a case at the case filling station will substantially counter-balance a filled case being elevated to stacked position at the stacking station.

Another object of the invention is to provide a unitary, compact and cooperative caser and stacker apparatus that is positioned above a continuously operated, uni-directional conveyor whereon empty cases are moved one at a time into the caser and each filled with a pattern of cartons, each filled case being moved on the conveyor to a case stacking station and the stacked cases being finally moved on said conveyor to a plant loading or a plant storage station; case movement being controlled by a series of conveyor located switches actuated by the cases.

A further object of this invention is to provide a simplified yet rugged case filling device wherein a pattern of cartons is supported in assembled condition directly under and within the case filling mechanism, said casing device including means for rendering the carton pattern support inoperative coincident with the initial operations of the carton gripping and the carton lowering mechanisms.

A further object of the invention is to provide in an apparatus having the foregoing characteristics an automatic means for sensing and rejecting defective cases which when actuated will permit the defective case to move directly through and out of the device.

A still further object of the invention is to provide a simplified control system for my caser and stacking device.

Still further objects of the invention will become apparent from the following specification taken in conjunction with the accompanying drawings which show a preferred embodiment of my invention; it being understood that various modifications could be made therein in order to handle other kinds, numbers and sizes of containers without departure from the terms of the appended claims.

In the drawings wherein like reference numerals and letters indicate like elements throughout the several views:

FIG. 1 is a front elevational view of my case filling and stacking apparatus, parts thereof being broken away and other parts shown in section.

FIG. 2 is a fragmental, side elevational view of the case filling device of my invention, parts being shown in section.

FIG. 3 is a section taken on line 33 of FIG. 2.

FIG. 4 is an enlarged section taken on line 44 of FIG. 3.

FIG. 5 is an enlarged, fragmental section taken on line 55 of FIG. 1.

FIG. 6 is a section showing a detail of the case entrance gate for my apparatus.

FIG. 7 is a side elevational view of the case stacking device for my apparatus, parts being shown in section.

FIG. 8 is an enlarged, fragmental view of the case exit gate for my apparatus, parts being shown in section.

FIG. 9 is a diagrammatic view of the electrical control system for the apparatus shown in FIGS. 1-8 of the drawings.

With reference to the drawings my apparatus, in general, is associated with a continuously operated, unidirectional case conveyor A comprising a pair of chains 15- 15 located within a track 16 in the floor 17 of a dairy plant, or the like; said chains being moved by a source of power (not shown) in the direction of the arrow 18 (FIG. 1). The initial station of my apparatus comprises a case filling device B positioned above the conveyor A and which is served by a milk carton receiving and transfer device C (FIGS. 2 and 3). A case loaded with its pattern of cartons is moved by the conveyor A from the case filling device B to a second station wherein the filled cases are vertically assembled by a case stacking device D and the stacked cases are then moved by the conveyor A to a plant loading or a plant storage station (not shown).

My apparatus is of unitary design and as shown in FIG. 1 is contained within a floor mounted frame 19 that straddles the conveyor A and is preferably constructed of vertical members 20, longitudinal members 21 and cross members 22 connected together as by welding to form a rigid machine base.

Now with reference to FIGS. 14 of the drawings the case filling device B comprises a vertically reciprocable carriage 23 that includes a pair of guide blocks 24--24 welded to the central part of a motor means which takes the form of an air cylinder 25, each block being slidable on a vertical guide rod 2626 suitably mounted at its respective ends to the frame 19. The upper end of the piston rod 27 for the air cylinder is fixed to the frame, flexible hoses 28 for introducing air under pressure into the cylinder ends to reciprocate the carriage 23 being connected to a source of air pressure provided from a machine control box 29. The carriage also has a vertical structural member 3030 Welded to the outer side of each guide block 2424, said members being connected at their lower ends as by welding to a carton gripping device 31, said device also being fixed on an extension 32 of the air cylinder 25.

With reference to FIG. 4 it will be noted that the carton gripping device 31 may comprise a head 33 having a double acting, air cylinder 34 mounted thereon, said air cylinder including a pair of laterally movable, piston actuated

jaws

35 and 36 which cooperate with depending

shoulders

36 and 37, respectively, on the head 33 to provide carton gable grippers for a pattern of milk cartons E assembled beneath the head 33.

The

movable jaws

35 and 36 are contracted into normally withdrawn positions by a spring return device located internally in the cylinders and are actuated to gable gripping positions with respect to the fixed jaws by air introduced under pressure into the central part of the cylinder.

The case filling device has a carton assembly and carton pattern station 38 located directly beneath and in vertical alignment with the gripper head 31, said pattern station having a pair of opposed carton support plates 39-39 each pivotally mounted at its outer end on the frame by means of a pivot pin 40-40 carried by a bracket 41-41 which in turn is connected to the frame by an extension member 42-42. As best shown in FIG. 4 a quick acting support and release device for each plate takes the form of a vertical rod 43-43 pivotally connected at its lower end in a yoke 44-44 fastened to its respective plate interiorly of and close to a pivot pin 40-40. The rod 43-43 for each plate has. its upper end slidable in a projection 45-45 on cylinder 25 (FIG. 1) and includes an adjustable stop 46-46 at its terminal end extension above the respective projections 45-45. When the case filling device is in its upper inoperative position the projections 45-45 will engage under the stops 46-46 and maintain and connected plates 39-39 in horizontal, carton pattern receiving positions, but with the initial movement of the filling device downwardly the projection will disengage the stops and the weight of the carton pattern will instantly pivot the plates downwardly out of the way of the descending carton pattern. It will also be noted with reference to FIGS. 2-4, inclusive, that fixed carton guide plates 47-47 are carried by members 42-42 to maintain the carton pattern in a compact condition. It will further be noted that when the cartons 38 are held upon the support plates 39-39 in an assembled position that their gables are located between the fixed and stationery jaws of the gripper mechanism 31 in position to be gripped by the jaws.

The carton receiving and transfer station C is best shown in FIGS. 1-3 of the drawings and may comprise a chain conveyor 48 adapted to move cartons 38 in single file onto a transfer table 49 that is on a level with the carton support plates 39-39 at the carton assembly and pat tern station 38. With reference to FIG. 3 it will be seen that as a row of say two cartons are moved into transfer position upon the table 49 the leading carton in the row tips a switch SW-l which operates a transfer device including a fixed air cylinder 50 having its piston rod 51 connected to an L-shaped carton pusher member 52. The air cylinder is adapted to reciprocate a distance equal to the width of the cartons assembled on the transfer table 49, such movement being limited by a control rod 53 movable with the pusher member and adapted to contact and trip a switch SW2 at the outermost limit of motion of the piston rod 51. The cylinder 50 continues to actuate the pusher member until the desired number of rows of cartons are assembled in a pattern upon the support plates 39-39 whereupon the leading row of cartons in the pattern contacts a switch SW3 which will initiate gripping momvement of the gripper 31 and initial movement of the case filling device B, such movements being momentarily delayed to allow for retraction of the pusher bar from the path of the case filling device.

As the case filling device is moved downwardly by the air cylinder 25, the pattern of cartons held by the carton gripping device will be deposited in an awaiting case 54 held in loading position upon the conveyor 15 by a pair of cooperative, L-shaped arms 55-55 mounted for horizontal movements toward and away from each other on vertical pivots 56-56 fixed to the frame in anysuitable manner (FIG. Upon opening movements of the stop arms the filled case 54 is released to be moved by the conveyor 15 until it is stopped by a pair of retractable arms 57-57 pivotally mounted on the frame at the stacker device D. These latter arms hold the filled case in position for eleva tion into stacked condition, as will now be specifically described.

With reference to FIGS. 1, 7 and 8 of the drawings the case stacker B comprises a vertically reciprocal elevator frame 58 slidable on guide rods 59-59 mounted at their ends on the frame 19. A pair of case lifting arms 60-60 are connected to the lower end of the elevator frame and are normally positioned beneath and one on each side of a conveyor chain 15 between said chain an dthe track 16. The vertical movements of the elevator frame 58 are related to the vertical movements of the vertically reciprocable carriage 23 at the case filling station B by a coordinating and counter-balancing means which preferably takes the form of a pair of flexible cables such as chains 61-61 each passed over a pair of longitudinally spaced apart

toothed idler sprockets

62 and 63 that are in turn suitably mounted on the frame 19. One end of each chain is connected to the member 30 on the carriage 23 while the opposite end of each chain is connected to the elevator frame 58. It will therefore be understood that as the carriage 23 is reciprocated by the air cylinder 25 to lower a pattern of cartons into an awaiting case and then return to normal position the coordinating chains will operate the elevator frame 58 to raise a filled case into stacked position in the stacker and return the elevator frame to normal position. Thus, the stacker elevator utilizes the energy created by the descending mass of cartons at the case filling station to aid in elevating the filled carton into a stacked position whilst the return movements of boh the elevator frame and the case filling carriage are accomplished in substantial equilibrium thus obtaining a minimum expenditure of power for the several operations.

The case elevator frame at the stacking station D is adapted to lift a filled case 54 from the conveyor 15 up between a pair of stack supporting dogs 64-64, and, as best shown in FIG. 8, each dog has a downwardly and outwardly extending pair of arms 65-65 fixed thereto which in turn are mounted on horizontal pivots carried by extension members 66-66 of the frame 19. When a case is moved upwardly between the dogs by the elevator said dogs are freely moved apart by the case and as the case moves above said dogs they fall by gravity into support positions beneath the case to support the stack, the dogs being held in stack supporting positions by suitable stops 67 on the extensions 66-66. Movement of the dogs '67 is coordinated with the case stop 57 by a pivoted linkage 68 whereby retracted positions of the dogs will result in moving the stops 57 out of case contacting positions relative to the conveyor A. A dog and stop release takes the form of an inverted V-yoke 69 secured by loose connections 70 to the dogs and connected at its upper end to a retracting air cylinder 71.

A case arresting entrance gate is located above the conveyor which initially contacts empty cases 54 and may comprise a depending arm 72 (FIG. 6) pivotally mounted on a piston rod 73 of .an air cylinder 74 positioned on the frame 19 beneath the transfer station C, said arm having a slot 75 therein for receiving a gravity link 76 pivoted at 77 to the frame and having a stop 78 on its outer free end beyond the arm 72. As shown in full lines in FIG. 6 the arm and link are at acute angles to one another, thus permitting the arm to hang freely for movement of the line of empty cases being urged forward on the conveyor A. When the air cylinder 74 is operated its piston rod 73 will move to the left as indicated by the dotted lines in FIG. 6, thus permitting the link 76 and arm 72 to assume right angular, rigid positions that will arrest movement of the line of cases while the holding arms 55'-55 are momentarily open.

With reference to FIG. 5 it will be seen that the arms -5555 are connected to the lower ends of L-shaped cranks 79-79, the inner end of said cranks being connected to the piston rod 73 of the air cylinder 74 by flexible link connections 80-80. As indicated in dotted lines in FIG. 5, actuation of the air cylinder 74 will move the arms 55-55 through the lever .and linkage to the dotted line positions which will permit the filled case to move therethrough upon the conveyor A, said air cylinder actuation also rigidifying the entrance gate to prevent forward movement of the line of cases on conveyor A.

In order to assure return of the case lifting arms 60-60 of the case stacker D to their inoperative positions beneath the conveyor A before a filled case 54 is moved on said conveyor from the case filling station B into stacking position I provide a retractible stop rod 81 (FIGS. 1, 3 and 5) guided at its lower end for vertical movement through an aperture in a transverse frame member 82 and having its upper end slidable in one projection 45 fixed on the carriage 23. The rod has a shoulder 83 thereon which defines its lower limit of motion at which limit the lower terminal end thereof projects into the path of a filled case, the rod having a shoulder 84 at its upper end which is engaged by the projection 45 to withdraw the rod from the path of the filled case when the carriage 23 and the lifting arms 60-60 are in their inoperative positions.

Operation The operation of my device will now be described with particular reference to the electrical diagram shown in FIG. 9 of the drawings wherein the parts are shown in normal apparatus shut down or inoperative conditions and a step down transformer 85 is depicted that energizes

lead lines

100 and 101 when a master switch 86 is manually closed. It is here assumed that an empty case 54 is initially being held in place on the place on the conveyor A beneath the case filling device B, by arms 55-55, a line of empty cases is on the conveyor A behind said case beneath the filling device, a filled case is on the conveyor beneath the stacker D, and that filled cartons 38 are being delivered to the transfer station C on conveyor 48 with their respective gables crosswise relative to the conveyor 48. As a row of cartons is completed on table 49 the switch SW-l will be momentarily closed, thus energizing a coil relay 87 which closes holding contact 87a and contact 87b which in turn actuates solenoid 88 to operate air cylinder 50 and its pusher 52 to slide a row of cartons onto the support plates 39-39 a distance equal to the overall width of the cartons. The gables of the cartons in the row are slid between the awaiting contracted or open jaws of the gripper 31 by such movement. As the pusher reaches its outer limit of motion switch SW-2 is momentarily opened to open holding contacts 87a and 87b and de-energize coil relay 87 and solenoid 88 to cause return of the pusher for the reception of the next row of cartons. This sequence is continued until the required number of carton rows have been fed onto plates 39-39 to make up the carton pattern E whereupon switch SW-3 will be closed loading coil relay 89 which closes holding switch 89a and normally opened switch contacts 891: and 89c which latter switches respectively operate the gripper head solenoid 90 for air cylinder 34 and makes the circuit to the elevator solenoid 91 for air cylinder 25 provided switch SW-S is closed by the presence of a case in filling position on the conveyor A. Thus the pattern of cartons will be gripped and the pattern lowered into the awaiting case by the carriage. As the carriage reaches its lowermost position one projection 45 on carriage 23 will contact and open switch SW-4 deenergizing solenoid 89 which opens

switch contacts

89b and 89c to stop descent of the elevator and releases the gable grippers to deposit the carton pattern in the awaiting case, respectively. Contact with switch SW4 also closes a low voltage line to solenoid 93 which momentarily operates air cylinder 74 to open arms 55-55 .and allow the conveyor A to initially move the filled case toward stacking position. The initial retraction of the arms 55-55 will open switch SW5 thus de-energizing solenoid 91 and causing the air cylinder 25 to raise the carton gripper and simultaneously lower the stacker to their inoperative positions, the filled case on the conveyor A being arrested and delayed by the stoprod 81 until such time as the stacker is in its lowermost position between the tracks 16-16.

When air cylinder 74 opens the arms 55-55 it also releases gate 72 which allows the leading case on the row of empty cases on conveyor A to be moved into filling position to thus .again close switch SW5 and condition its circuit for the next operation. As the filled case reaches stacking position it closes switch SW-6 which energizes solenoid 94 that in turn operates air cylinder 74 to close arms 55-55 and rigidity entrance gate lever 72. As has been stated each time a carton pattern is lowered by the carriage into an awaiting case at the filling station a filled case is raised into stacked position by the stacking device by reason of the means interconnecting the carriage and the stacking device.

The foregoing sequence of operation is repeated until a complete stack of filled cases is present in the stacker at which time switch SW-7 is closed to energize coil relay 95 which when energized closes normally opened holding contacts 95a, contacts 95b and opening closed contacts 95c. The closing of contacts 951; energizes solenoid 96 which operates air cylinder 71 retracting the stack supporting dogs 64-64 and simultaneously opening exit gate arms 57-57 which allows the stacked cases to be lowered onto the conveyor A, the conveyor carrying the stacked cases out of my apparatus, said stack of cases closes switch SW-8 which de-energizes coil relay 95 allowing the stack support dogs 64-64 to return to operative position and closing exit gate arms 57-57.

Delay means is provided to assure delay operation of the carton receiving and transfer device C until the case filling device is in its upper inoperative position, such means comprising a normally closed switch SW-9 (FIGS. 2 and 9) interposed in the circuit of coil relay 87 which is opened upon initial downward movement of the carriage and remains opened until return of the carriage to its upper inoperative position.

My apparatus has a defective case sensing and rejecting device comprising a vertical rod 97 (FIG. 1) carrying at its lower end a horizontally disposed U-shaped spider 98 disposed superjacent the tops of the carton pattern E held by the jaws of the gripper head. In the event the pattern of cartons being lowered by the filling device would meet an obstruction caused by a defective case, or for some other reason, the cartons in the pattern would be somewhat crushed by the stoppage thus moving the rod 97 upwardly thereby closing switch SW-10 that in turn actuates coil relay 99 and closes normally open contacts 99a and 99b, the closing of contacts 99a causing actuation of solenoid 94 and operation of air solenoid 74 to open case stop arms 55-55 to allow the defective case to move on conveyor A. As SW5 is on one arm 55 it will be opened thus causing return of the elevator carriage to its inoperative upper condition and return of the stacker to its lower position.

At the time a defective case is rejected from the case filling device another set of normally open contacts 99b are closed energizing coil relay 95 to operate the air cylinder 71 thus simultaneously operating the stack dogs 64-64 and exit gate 57-57 to permit whatever stack of cases are in the stack at the time of the defective case rejection to be carried out of my apparatus, the defective and rejected case being allowed to enter the stacker as the topmost case in the next stack made in the stacker for ready detection and removal.

Actuation of coil relay 99 will also open normally closed contacts 950 which will return exit stop arms 57- 57 and stack dogs 64-64 to normal operative positions since the defective case at that time would have closed switch SW-6 to energize solenoid 94 and said circuit thereto should be de-energized momentarily to allow an empty case to pass entrance gate 72 and be positioned in the filling device in the place of the defective and rejected case.

Having thus described my invention, what I claim as new is:

1. In a case filling and case stacking machine the combination of a carton assembly station, a carton gripping device adapted to periodically lower the assembled cartons into a case, a case stacking device adapted to periodically receive a carton filled case and raise it into stacked position, and counter-balancing means interconnecting the carton gripping device to the case stacking device.

2. In a case filling and case stacking machine the combination of a vertically reciprocable carton gripping device, motor means for reciprocating the carton gripping device, a carton assembly station subjacent the carton gripping device, said device being adapted to periodically lower assembled cartons into a case, a case stacking device adapted to periodically receive a carton filled case and raise it into stacked position, and counter-balancing means operatively connecting together the carton gripping device and the case stacking device.

3. In a case filling and case stacking means the combination of a unidirectional case conveyor, a carton assembly station positioned above the conveyor, a case stop means adapted to locate a case on the conveyor beneath the carton assembly station, a vertically reciprocable carton gripping device, motor means for reciprocating the gripping device and adapted to periodically lower an assemblage of cartons into the positioned case, a case stacking device positioned above the conveyor adjacent and downstream from the carton assembly station, said case stacking device being adapted to periodically receive a filled case from the conveyor and raise it to stacked position above the conveyor, and counter-balancing means operatively connecting together the carton gripping device and the case stacking device.

4. In a case filling and case stacking means as set forth in claim 3 wherein the counter-balancing means comprises an idler located vertically above the carbon gripping device, an idler connected vertically above the stacking device, and a flexible cable means having each end connected to a device and having an upper reach movable over said idlers.

5. In a case filling and case stacking means as set forth in claim 4 wherein the flexible cable means is a chain and the idlers are each a free running sprocket gear.

6. In a machine for loading a carton pattern into a case, the combination of a frame, a vertically reciprocable carriage on the frame, a carton gable gripping device on the carriage, a carton pattern assembly station subjacent the gable gripping device including a pair of opposed carton support plates, pivot means on the frame outside the assembly station pivotally mounting the support plates, a support rod connected to each plate inside and closely adjacent the pivot means, a slidable connection between the carriage and the upper end of each rod, and a stop means on each rod engagable by the carriage to maintain each rod and plate in carton supporting position.

7. In an apparatus of the class described a continuously moving, unidirectional case conveyor, a carton filling station positioned above the conveyor, retractable stop means adjacent the conveyor at the filling station normally retaining a line of empty cases against motion on the couveyor and adapted to position the leading case in the line in carton filling position, a carton pattern assembly device above the conveyor at the filling station, a vertically reciprocal carton pattern gripping device, motor means for lowering the carton pattern from the carton assembly device into the leading case held on the conveyor by the stop means, control means responsive to the presence of a full complement of the cartons in the leading case reversing the movement of the motor means and simultaneously releasing the carton pattern gripping device; said control means retracting the case stop means to permit movement of the filled case on the conveyor, normally inoperative case entrance gate means, means operable with the retraction of the stop means for rendering the case entrance gate means operable, a case stacking station above the conveyor and located downstream from the case filling station, a retractable case exit gate adjacent the conveyor at the case stacker station adapted to hold the filled case in stacking position, a vertically reciprocal case raising and case stacking elevator above the held filled case, counter-balance means connecting together the case stacking elevator and the carton pattern gripping device, and means responsive to the accumulation of a stack of filled cases at the stacking station lowering the elevator with the stack onto the conveyor and simultaneously retracting the case exit gate to permit movement of the stack on the conveyor.

8. A machine for transferring a pattern of gabled cartons into a case comprising a continuously moving, unidirectional case conveyor, a frame disposed over the conveyor, a retractable case stop means adjacent the conveyor within the confines of the frame, a transfer table adjacent the frame, means accumulating a row of cartons on the table, a pair of opposed carton pattern support plates, each pivotally mounted at its outer side on the frame and above the case held by the stop means on the conveyor, normally operative means for maintaining the support plates flush with the table, reciprocating pusher means adapted to periodically feed a pattern of cartons onto the support plates, a vertically reciprocable carriage above the plates, a gable gripping means on the carriage having opposed expanded jaws disposed on a level to receive between them the gables of the pattern of cartons fed onto the plates, means responsive to the completion of the pattern of cartons on the plates for rendering the gripping means operative, delayed action means made operative to render the support plates inoperative and then lower the carriage and deposit the carton pattern into the case, and means operative upon the deposit of the carton pattern into the case retracting the stop means to permit the conveyor to carry away the filled case.

9. In apparatus of the class described a floor positioned, continuously moving, unidirectional case conveyor, a floor mounted frame positioned over a portion of the conveyor, retractable stop means normally disposed in the path of a case on the conveyor and adapted to position said case within the lower confines of the frame, a releasable carton pattern assembly device on the frame in vertical alignment with the empty case, a carriage mounted on the frame for vertical reciprocation above the carton pattern assembly device, a carton pattern gripping device depending from the carriage, power means for lowering the carton pattern from the carton assembly device into the case, control means responsive to the presence of a full complement of cartons in the case reversing the movement of the power means and simultaneously releasing the carton pattern gripping device, means responsive to the actuation of the control means for retracting the case stop means to permit movement of the filled case on the couveyor, a case stacking station on the frame above the conveyor, a retractable case exit gate across the conveyor subjacent the case stacking station adapted to hold the filled case in stacking position, a vertically reciprocal case raising and case stacking elevator above the held filled case, coordinating, control means between the case stacking elevator and the carriage, and means responsive to the accumulation of a stack of filled cases at the stacking station lowering the elevator with the stack onto the conveyor, and means simultaneously retracting the case exit gate to permit movement of the stack on the conveyor and out of the frame.

10. In apparatus of the class described in claim 9 wherein the retractible stop means comprises a pair of barrier members, means mounting each of the members on the frame on opposite sides of the conveyor for lateral movement toward and away from each other, and reversible motor means for operating the barrier members in unison.

11. In apparatus of the class described in claim 10 wherein a case sensing control switch is disposed for actuation by the empty case when said case is held in carton filling position by the retractible stop means.

12. In an apparatus of the class described a unidirectional case conveyor, a carton filling station positioned above the conveyor, retractible stop means adjacent the conveyor at the filling station and adapted to position the leading case in the line in carton filling position, a carton pattern assembly device above the conveyor at the filling station, a vertically reciprocal carton pattern gripping device, motor means for lowering the carton pattern from the carton assembly device into the leading case held on the conveyor by the stop means, control means responsive to the presence of the carton pattern in the leading case reversing the movement of the motor means and simultaneously releasing the carton pattern gripping device, said control means retracting the case stop means to permit movement of the filled case on the conveyor, a normally inoperative case entrance gate means, means operable upon retraction of the stop means rendering the case entrance gate means operable to momentarily delay movement of the line of empty cases by the conveyor, and a conveyor positioned control means, coordinated with the movement of the filled case by the con veyor beyond the carton filling station returning the retractible stop means and the case entrance gate means to normal positions.

13. In apparatus of the class described in claim 12 wherein the case stop means and the case entrance gate means are operated by a single reversible motor, and operating means connecting said motor to the control means.

14. In the apparatus set forth in claim 7 wherein a defective carton sensing means is disposed adjacent the carton pattern gripping device, and means made operative by the carton sensing means actuating the control means and the case exit gate to permit movement of the case with the defective carton out of the apparatus.

15. In an apparatus of the class described a unidirectional case conveyor, a carton filling station positioned above the conveyor, retractible stop means adjacent the conveyor at the filling station for retaining an empty case against further motion on the conveyor and adapted to position said case in carton filling position, a carton pattern assembly device above the conveyor at the filling station, a vertically reciprocal carton pattern gripping device, motor means for lowering the carton pattern from the carton assembly device into said case on the conveyor, control means responsive to the presence of the carton pattern in said case reversing the movement of the motor means and releasing the carton pattern gripping device, said control means retracting said stop means to permit further movement of the filled case on the conveyor, case entrance gate means which is operable to momentarily delay movement of an empty case by the conveyor into the carton-filling position while said stop means are retracted, and control means coordinated with the move ment of the filled case by the conveyor beyond the carton filling station for returning said retractible stop means to its case-retaining position and for moving said case entrance gate means to a position where it no longer delays movement of an empty case.

References Cited UNITED STATES PATENTS 2,681,171 6/1954 Brown et a1 5362 2,946,164 7/1960 Potts et a1 53247 X 2,951,323 9/1960 Haab 53166 X 2,957,287 10/ 1960 Cella 5362 X 3,047,990 8/1962 Du B rofi 5362 X 3,069,823 12/1962 Schmidt 5362 X TRAVIS S. MCGEHEE, Primary Examiner.