Carton Lidding Machine

Abstract

A carton lidding machine particularly suited for use in lidding open-top cartons, characterized by a horizontally disposed carton transporting conveyor extending through a lidding station at which conveyed cartons receive lids formed from prescored blanks. A particular feature of the invention resides in the provision of a vertically reciprocable elevator located at the lidding station adapted to be operated in a manner such that each carton is lifted from the conveyor and forced into lid-forming engagement with a prepositioned, prescored blank of a planar configuration, and then returned to the conveyor, in stepped progression, for accommodating a sequential stapling of the thus formed lid to the walls of the carton.

Description

The invention relates to lidding machines and more particularly to an improved lidding machine suited for use in forming and securing prescored lid blanks about the openings of serially presented open-top cartons, whereby carton lids are formed in place as carton closing operations are completed.

A large number of machines capable of applying lids, covers and the like to open and filled cartons currently are available. Among this number are machines which serve to form prescored lids, about the openings of cartons of the type commonly called open-top cartons. Quite frequently, lids are presented to filled cartons in the form of prescored blanks having planar configurations. When the carton is of an open-top variety the blanks are extended across the carton openings and then down-folded along score lines in a manner such that the peripheral portions of the lids engage the vertical side walls of the cartons. Such machines often require cartons to be conveyed along a path having normally related, horizontal and vertical path components so that the cartons in an upright and open condition, initially are conveyed in a horizontal direction to a lidding station and then elevated, while being maintained in their upright condition, through prepositioned lid blanks for purposes of down-folding and thus forming the blanks about the cartons. A vertically disposed chute then is provided for purposes of completing the sealing of the thus formed lids about the openings of the cartons. A machine of this general type is more fully disclosed in U.S. Letters Patent No. 3,501,895, issued Mar. 24, 1970.

While machines of the general type disclosed in the aforementioned United States Letters Patent, in most instances function quite satisfactorily for purposes of forming and applying prescored lid blanks to filled cartons and the like the structure normally utilized tends to be rather bulky and complex. This particularly is true where the cartons are filled with materials possessing a significant mass. For example, where the material filling the cartons includes products, such as eviscerated poultry and other meat products, the weight load imposed on the machine is significant. In the event large numbers of the cartons simultaneously are handled in a vertical chute, the combined weight tends to impede satisfactory operation.

Therefore, there currently exists a need for a practical, simplified and efficient lidding machine which can readily be associated with carton filling machines and be employed to form and secure prescored lid blanks about the opening of filled open-top cartons.

It is therefore an object of the instant invention to provide an improved lidding machine.

Another object of the invention is to provide and improved lidding machine adapted to apply prescored lid blanks to filled, open-top cartons.

Another object of the invention is to provide an improved lidding machine adapted to form and secure lid blanks to open-top cartons in a manner such that the lids instantaneously are affixed to the side walls of the cartons.

Another object of the invention is to provide an improved lidding machine wherein open-top cartons serially are elevated into forming engagement with prescored blanks, lowered and serially discharged from the machine.

Another object is to provide an improved lidding machine through which open-top cartons serially are advanced, elevated into lid-forming engagement with a prescored lid blank and then stapled for securing thereto the thus formed lid.

Another object is to provide in a carton lidding machine a lidding station having a lid blank feeder for positioning a prescored lid blank directly above the opening of an open-top carton, a carton elevator adapted to receive and elevate the open-top carton into lid-forming engagement with the lid blank and then lower the carton in incremental advancement for horizontal discharge, and a plurality of staple guns for driving a series of staples along the periphery of the thus formed lid for securing the lid in place as the carton is lowered.

Another object is to provide an improved lidding machine including therein a unique arrangement of lidding structure through which prescored lid blanks rapidly and efficiently are applied to openings of filled open-top cartons for thus completing carton filling and closing operations.

These and other objects and advantages of the instant invention are achieved through a simplified machine which employs a horizontally extended conveyor for delivering a series of filled, open-top cartons through a lidding station wherein the cartons serially are elevated into lid-forming engagement with pre-positioned, prescored lid blanks and operated upon in a manner such that the blanks are formed about the openings of the cartons and are secured to the vertical side walls of the cartons through a plurality of staples applied as the elevated cartons are returned to the conveyor, in incremental advancement, and horizontally discharged from the lidding station.

FIG. 1 is a front elevation of a machine which embodies the principles of the instant invention depicting a preferred relationship established between a carton transporting conveyor and an associated carbon lidding station.

FIG. 2 is a fragmented, top plan view of the lidding station of the machine illustrated in FIG. 1.

FIG. 3 is a sectioned plan view taken generally along line 3--3 of FIG. 1.

FIG. 4 is a sectioned side elevation, taken generally along line 4--4 of FIG. 2.

FIG. 5 is a sectioned end elevation, taken generally along line 5--5 of FIG. 1.

FIG. 6 is a partial perspective view of selected portions of the carton elevator and lid forming mechanism employed at the lidding station illustrated in FIGS. 1 through 5.

FIG. 7 is a single-line, diagrammatic view depicting a practical control circuit employed in achieving sequential control for the operation of the machine which embodies the principles of the present invention.

FIG. 8 is a perspective view of an open-top carton and associated lid blank, arranged in their relative positions assumed at the lidding station of FIGS. 1 through 7, just prior to closing the carton.

FIG. 9 is a perspective view of a carton closed by the machine of the instant invention.

FIG. 10 os a perspective view of a switch actuator employed in activating the circuit illustrated in FIG. 7.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the drawings wherein like reference characters designate like or corresponding parts throughout the several views, there is shown in FIG. 1 a carton lidding machine which embodies the principles of the instant invention. It is intended that the term carton, as herein employed, encompass containers of various types including boxes, bins and similar receptacles, without regard to the specific material from which the container is fabricated.

The machine includes a frame, generally designated 10, fabricated of any suitable material. In practice, the frame 10 is of an all-welded rail construction and is fabricated from extruded shapes having suitable strength characteristics. Since the specific configuration of the frame 10 primarily is a matter of convenience, a detailed description is omitted in the interest brevity. However, it is to be understood that the frame 10 generally is of an upright configuration and is adapted to be mounted on any suitable supporting surface, such as a supporting floor and the like.

Briefly, the lidding machine of the instant invention includes a lid feeding mechanism, generally designated 12, which serves to deliver prescored lid blanks 14, of a planar configuration, to a lidding station 16, while open-top cartons 18 serially are delivered to the lidding station 16 by means of an intermittently operated conveyor 20. As the lid blanks 14 are delivered to the lidding station 16, they are disposed in a horizontal plane and are caused to register with the cartons 18. Each of the cartons 18 is, in turn, lifted by an elevator 22, and forced into lid-forming engagement with the registered lid blank 14. As the lid blank 14 is engaged, it is carried through an opening defined by a plurality of angularly related plows 24, FIGS. 4 and 5. These plows serve to down-fold peripheral portions 25 of the blank 14, along score lines 26, for thus forming a lid 28, FIG. 9. The lid 28 then is secured to the vertical side walls of the carton 18 through a multiplicity of staples 29, FIG. 9, affixed thereto through an array of a plurality of staple guns 30 operated in a predetermined sequence. Once the lid 28 has been secured to the carton 18, the thus closed carton 18 again is lowered and redeposited on the conveyor 20, whereupon it is conveyed in a horizontal direction and thus discharged from the lidding station 16.

As best illustrated in FIG. 10, each of the lid blanks 14 is delivered to the lidding station 16 along a substantially horizontal surface of a table 32. As a practical matter, the table 32 is formed as a terminal portion of a blank magazine, not shown.

The table 32 preferably is provided with a feed-coupling, not designated, which includes a coaxially related pair of driven rollers 34 and a pair of coaxially related spring-biased backup rollers 36. The pairs of rollers 34 and 36 are mated to establish therebetween a pair of bights 37 for receiving and singly delivering the lid blanks 14 to the lidding station 16.

As a practical matter, the pair of feed rollers 34 is driven through a suitable drive train 38, which can, where desired, include a plurality of suitable belts trained about drive sheaves and operatively associated with a drive motor 40. Since the drive train 38 is deemed to be a matter of convenience, a detailed description thereof is omitted in the interest of brevity.

In practice, the pair of drive rollers 34 is supported by a shaft 41 journaled in a pair of spaced bearings 42 fixed to the frame 10, while the pair of backup rollers 36 is supported for rotation about a shaft 43 fixed at the distal end of a laterally extended lever arm 44. The lever arm 44, in turn, is spring-biased for pivoted oscillation about a pivot pin 46 fixed to the frame 10 through a suitably supported journal 47. The pair of backup rollers 36 continuously is urged into engagement with the pair of drive rollers 34, by means of a suitable compression spring 48, so that the blanks 14 are readily accepted within the bights 37 and singly passed through the feed-coupling, as their lower surfaces frictionally are engaged by the peripheral surfaces of the rollers of the pair of drive rollers 34 operating at speeds dictated by the drive train 38.

Disposed in coplanar relationship with the upper surface of the table 32, and with the bights 37 of the pairs of rollers 34 and 36, there is provided a pair of mutually spaced, coplanar lips 50, FIG. 4, which serve to receive and vertically support the lid blanks 14 as they are delivered from the bight 37 and into registry with openings of open-top cartons 18 as the cartons are advanced into registry with the elevator 22 by the conveyor 20.

The conveyor 20 includes a pair of endless conveyor chains 52 having upper runs seated in parallel tracks, not designated. The chains 52 are trained about multiple pairs of coaxially related sprockets 54, which are supported by suitable sprocket shafts 56 and in a manner such that the chains 52 are arranged in a side-by-side coplanar relationship for providing a pair of coplanar reaches extending horizontally through the lidding station 16 so that open-top cartons 18 are, in operation, delivered to the lidding station 16 for receiving a lid 28 and, subsequently, discharged from the station as the chains 52 of the conveyor 20 drivingly are advanced in a horizontal direction.

The chains 52 are driven in advancement by a drive train 58. As illustrated, the chains 52 are coupled through the drive train 58 to a motor 60, of any suitable design. The drive train 58 preferably includes a selectively energizable clutch 62 interposed between the motor 60 and an input drive sprocket 64. This sprocket receives thereabout a drive chain 66 which serves to couple the sprocket 64 with a driven sprocket, not designated, fixedly mounted on one of the shafts 56. Since the specific design of the drive train 58 employed in driving the conveyor 20 is deemed a matter well within the purview of the art, a detailed description is omitted in the interest of brevity. However, it is important to understand that the conveyor 20 is, in practice, intermittently advanced through the lidding station 16 in a manner which delivers the cartons at appropriate intervals and accommodates an application of a lid blank 14 thereto during established dwell periods of appropriate durations.

While the particular manner in which the open-top cartons 18 are erected and filled forms no specific part of the instant invention, it is however, to be understood that the cartons 18 in practice are deposited on the conveyor 20 in an opened and filled condition in order that the cartons can be delivered in an upright disposition into registration with a lid blank 14, as the blank is supported by the lip 50. Furthermore, the lid blank 14 and carton 18 are registered with the elevator 22, which is adapted to raise each of the cartons 18 into engagement with serially supported lid blanks 14.

The elevator 22, as best illustrated in FIG. 6, includes a vertically reciprocable frame 68, which is guided in vertical reciprocation by a plurality of guide rollers 69 for thereby effecting a raising and lowering of a horizontally disposed carton supporting platform 70 mounted thereon. As a practical matter, vertically disposed rail surfaces 71 are provided for supporting the rollers 69 as the frame 68 is reciprocated in vertical directions.

The platform 70 is extended across the width of the conveyor 20 and is of a length consistent with the length of the cartons 18 being handled. This platform includes a center panel 72 adapted to pass between the upper reaches of the conveyor chains 52, whereby the center portion of the bottom surface of each filled carton 18 is engaged by the panel 72 as the frame 68 is advanced in an upward direction. Additionally, the supporting platform 70 includes a pair of lateral wing panels 74 which has an upper planar surface disposed in a coplanar relationship with the upper surface of the center panel 72. These panels are so spaced, with respect to the center panel 72, as to accommodate a passage therebetween of the individual chains 52 of the conveyor 20 as the platform 70 is elevated and lowered.

Consequently, it should be apparent that the center portion of the bottom surface of each carton 18, as it is elevated by the elevator 22, is engaged by the center panel 72 of the platform 70, while the peripheral side portions of the bottom surface of each of the cartons simultaneously are engaged by the wing panels 74 for imparting vertical support to the longitudinal peripheral portions of the cartons 18 as the cartons are elevated by the elevator 22.

The frame 68 of the elevator 22 is of a substantially rectangular configuration, and includes four upright legs 76 upon which are mounted guide rollers 69. These legs are interconnected through a plurality of rungs 78, FIG. 6, appropriately coupled with the legs 76 through any suitable coupling means, including welds and the like for imparting rigidity thereto. Rigidly fixed to the upright legs 76 is a plurality of horizontally extended and transversely oriented beams 80 upon which is mounted the center panel 72 of the platform 70. A pair of vertically extended stanchions 82 are rigidly coupled to the transverse beams 80. At the uppermost distal end of the stanchions 82 there is secured the panel 72. While various arrangements can be employed in supporting the wing panels 74, it has been found practical to provide a plurality of gusset plates 84, extended from the legs 76, for this purpose. Accordingly, gussets 84 are welded to the uppermost end portions of the legs 76 to engage the wing panels 74 for rigidly coupling these panels within the elevator 22.

In order to advance the elevator 22 in a vertical direction, a pair of cam followers 86 is provided at opposite ends of the frame 68. Preferably, the followers 86 are formed as rollers rotatably supported on a pair of transversely oriented support shafts 88. Disposed in driving engagement with the peripheral surface of the rollers 86 is a plurality of lifting cams 90 positioned at opposite ends of the elevator 22 and rotatably supported by a drive shaft 92 journaled to the frame 10 through suitable journal blocks 94.

The peripheral surfaces of the cams 90 are so disposed and eccentrically configured, relative to their axes of rotation, as to engage and act against the peripheral surfaces of the followers 86 for thereby controlling the vertical advancement of the frame 68. Each of the cams 90 includes a surface having a first portion, which serves to upwardly advance the frame 68 as the shaft 92 is driven through its first 90.degree. of rotation, a second portion, which supports the frame 68 in a substantially stationary disposition during the next substantially 180.degree. of rotation of the shaft 92, and a third portion, which serves to effect a downward advancement of the frame 68 during the next 90.degree. of rotation of the shaft 92. Additionally, it is important to note that the periphery of each of the cams includes a stepped portion, designated 96, located midway of the second portion of the cam's surface. The stepped portion permits the frame 68 to drop slightly to thus establish two dwell periods as the cams 90 are driven in rotation by the shaft 92.

The shafts 92 are driven in synchronous rotation through a drive train 98, which includes a pair of drive chains 100 and 101. The chain 100 is trained about a driven sprocket 102 fixed to one of the shafts 92, and an input sprocket 104. The input sprocket 104, in turn, is fixed to an input shaft 105 which is driven through a suitable clutch 106 by means of an electrically energizable motor 108 mounted on the frame 10. If desired, the clutch 106 and motor 108 can be of a design similar to the clutch 62 and motor 60. Additionally, the drive chain 101 is trained about a pair of radially spaced sprockets 109, each being fixed to one of the shafts 92 in order to impart synchronous driven rotation to the shaft. Hence, the cams 90 are driven in synchronous rotation, whereby the frame 68 of the elevator 22 cyclically is caused to ascend and then intermittently to descend in the manner prescribed by the configuration of the periphery of the cams 90.

As best illustrated in FIG. 6, immediately above the plane of the lip 50, there is provided a presser unit, generally designated 110, which serves as a back-up unit in order to assure a seating of the lid blank 14 with respect to the opening of each of the open-top cartons 18, as the carton is advanced into engagement therewith. The presser unit 110 includes a substantially rectangular presser frame 112 formed of any suitable structural material, such as extruded shapes and the like.

In practice, the presser frame 112 is suspended from a plurality of vertically extended hangar rods 114. These rods extend vertically through suitable openings, not designated, formed in a guide frame 116, and terminate in vertically protruding distal portions 118. Each of these portions receives a concentrically related compression spring 120 so mounted on the hanger rods 114 as to continuously urge the frame 112 in a downward direction. To achieve this effect, the distal ends of the rods 114 are extended through suitable openings, not designated, formed in a hangar frame 122, FIGS. 4 and 5, fixed to the frame 10 in any suitable manner. At the uppermost end of each of the rods 114 there is provided a screw-threaded nut 124 which acts as an annular stop for limiting the downward displacement of the rods 114 through the frames 116 and 122, for thereby limiting the downward displacement of the presser frame 112. While each of the springs 120 is coupled with an associated rod 114 through an annular stop 126 fixed to the body thereof, the uppermost end of the spring 120 is secured against axial displacement relative to the frame 122 by any suitable means, not shown. If desired, washers and the like may be interposed between the springs and the frame in a manner which accommodates passage of the rods but arrests displacement of the springs 120. Therefore, as each of the cartons 18 is elevated by the elevator 22, for thus causing the carton 18 to ascend into engagement with a prepositioned lid blank 14, continued upward advancement of the carton tends to transport upwardly the blank 14 into engagement with pressure unit 110, whereupon the blank is seated in engagement with the upper surfaces of the carton 18, for thus assuring that the blank 14 and the carton 18 are appropriately mated as the carton and the blank are advanced between the opposed surfaces of the plow 24.

The plows 24 also are of any suitable design. However, as illustrated, the plows 24 are configured to conform to four normally related, laterally extended elongated beams 127 which substantially circumscribe the presser frame 112 of the presser unit 110. As a practical matter, each of the beams 127 includes a laterally extended foot 128, one of which terminates in a depending stop 130, FIG. 5, for engaging the vertical peripheral edge surface of each lid blank 14 as it is advanced into registry with the lidding station 16. A pair of beams 127 includes guides 132 which serve to guide the blanks as they are received by the lips 50. As a practical matter, the lips 50 also are supported by the guides 132. The fourth beam, as best illustrated in FIG. 5, includes an upturned lip 134 for accommodating a passage of the blanks 14 from the bights 37 of the rollers 34 and 36.

Each of the plows 24 further includes a vertical body 136. The opposed faces of the bodies 136 are adapted to engage the external surface of the lid blank as the carton 18 is advanced upwardly between the beams 127 of the plows 24. If found to be practical, the plows 24 can include a flared surface 138 which tends to effect a down-folding of the peripheral portions of lid blank 14 as the carton 18 is advanced upwardly between the plows.

Hence, it can be appreciated that by driving the elevator 22 in a reciprocating fashion, through an appropriate operation of the cams 90, each of the open-top cartons 18 is caused to engage a blank 14, as it is supported by the lips 50, and the blank and the carton then are forced to pass between the plows 24, whereupon a down-folding of the peripheral portion 25 of the blank 14, about its score lines 26, is achieved.

While not illustrated, the cartons 18 can be of a type which includes an adhesive for securing peripheral portions 25 of the blanks 14 to the carton walls as they are down-folded by the plows 24. Hence, the lids 28 can adhesively be secured to the cartons 18. However, as illustrated, it is preferred that each of the lids 28 be secured to an associated carton 18 through a simultaneous operation of the plurality of staple guns 30.

The stapling guns 30 are of a commercially available design. Preferably, the guns 30 are of a type which are pneumatically actuated and clip-fed by a roll or clip 140. Each of the rolls 140 is supported within a suitable magazine 142 an operatively associated with a gun 30 in a manner such that the roll serves to feed the staples 29 downwardly into the pneumatically actuated staple gun. Since the particular staple gun employed forms no particular part of the instant invention, a detailed description of the gun is omitted, also in the interest of brevity.

However, the array of guns 30 is adapted to effect a simultaneous driving of the staples 29 into the down-folded peripheral portions 25 of each lid 28 for thereby securing the lid 28 to vertical side walls of the carton 18. To accommodate such an arrangement, the guns 30 are provided in four pairs and disposed adjacent to the vertical side walls of the carton 18, as the carton is supported in its elevated disposition by the elevator 22. A plurality of openings 144 are formed in the vertical body portions 136 of the plows 24 in order to permit the staple guns 30 to communicate with the down-turned peripheral portion 25 of the lid 28 whereby driving of the staples is accommodated.

In order to assure that the open top cartons 18 properly are aligned, as they horizontally are advanced into the lidding station 16, by the conveyor 20, a plurality of parallel guide rails 146 are extended along opposite sides of the conveyor 20, through the lidding station 16, and serve to engage the vertical side walls of each of the cartons 18 as the cartons are advanced by the conveyor 20. Consequently as each carton 18 is brought into registry with a lid blank 14 supported within the carton lidding station 16, the guide rails 146 assure that proper transverse orientation of the carton, relative to the blank 14 and the plows 24, is achieved.

In order to assure that a proper longitudinal orientation of each carton 18 is achieved as the cartons serially are caused to register with the blanks 14, a switch actuator 148, FIG. 10, is disposed in the path of each of the cartons, for engaging the leading wall of the carton, and responsively terminating operation of the conveyor 20. This horizontal advancement of each of the cartons 18 is arrested at an appropriate instant for thus registering the carton 18 with respect to a blank 14 and to the plows 24.

As best illustrated in FIGS. 7 and 10, the actuator 148 includes an intercepting roller 150 disposed directly within the path of cartons 18 as they advance by the conveyor 20. The intercepting roller 150 is mounted within a suitable bracket 152, welded or otherwise coupled to a T-bar 154. The T-bar 154 includes a horizontally extended body 156 and a vertical depending stem 158. The body 156 is supported for rectilinear reciprocation along a path having a primary component extending horizontally, while the stem 158 is supported for reciprocating displacement along a path having a primary component extending in a vertical direction. Consequently, it can be readily appreciated that the T-bar 154 is adapted to be reciprocated along a path having normally related components, whereby the intercepting roller 150 can be advanced and retracted in opposed horizontal directions and elevated and depressed in vertical directions.

In order to guide the T-bar 154, as it is reciprocated in both vertical and horizontal directions, there is provided, near the juncture of the body 156 and stem 158, a laterally extended guide pin 160 which guidingly couples the T-bar to a pair of mutually spaced, parallel plates 162 arranged at opposite sides of the T-bar. The pin 160 is received within a pair of right-angle slots 164 formed in the plates 162, while the plates are spaced a distance sufficient to impart lateral stability to the T-bar and supportingly guide the T-bar 154, as it is caused to reciprocate along either component of its paths. In practice, a plurality of appropriately mounted tension springs 166 are coupled to the T-bar 154 through a plurality of coupling pins 167. The springs 166 are united with the plates 162 in a manner such that the T-bar is urged in directions appropriate for causing the intercepting roller 150 to so position itself as to engage each of the cartons 118 as it is advanced into the lidding station 16 through a driven advancement of the conveyor 20.

Disposed adjacent to the actuator 148, FIG. 7, there is a pair of limit switches designated 168 and 180 which impart sequential control of the machine. The limit switch 168 is a normally-open switch electrically coupled between a source of electrical potential, not shown, and a solenoid, also not shown, mechanically coupled with the clutch 106. This clutch is adapted to effect a driving relationship between the motor 108 and the drive sprocket 105, once the switch 168 is closed. The drive train 66, on the other hand, is controlled by the limit switch 170 which is a normally-closed switch operatively interconnected in an electrical circuit extending between the aforementioned source of electrical potential and a solenoid, also not shown, disposed in operative association with the clutch 62. When the limit switch 168 is closed, through an engagement with the T-bar 154 of the actuator 148, the solenoid of the clutch 62 simultaneously is caused to disengage for thereby interrupting the driving relationship established between the motor 60 and the drive sprocket 64 so as to interrupt the advancement of the conveyor 20, as operation of the elevator 22 is initiated in response to a closing of the switch 168.

It is to be understood that the motors 60 and 108 could be energized and de-energized in response to an opening and closing of the switches, in lieu of employing the solenoid actuated clutches 62 and 106. In such instances, the clutches 62 and 106 can be eliminated and a direct drive established from the motors to the associated driven drive train components. However, the motors 60 and 108 preferably are continuously driven in order to avoid an overloading as they are rendered effective for intermittently driving the conveyor 20 and the elevator 22.

In order to establish synchronous control over the operation of the machine, each of the switches 168 and 170 is coupled with its associated solenoid through one relay 172 of a pair of such suitable relays. The relays 172 function as holding circuits and achieve a holding function for the appropriate solenoids employed in controlling the clutches 62 and 106, as the associated switches are opened and closed. Since solenoids are notoriously old a detailed description thereof is omitted in the interest of brevity. However, it is to be understood that each of the relays is a bi-stable device, the state of which is switched in response to an electrical signal delivered thereto from a given limit switch.

In order to de-energize the solenoid of the clutch 106, and simultaneously again energize the solenoid of the clutch 62, a second pair of limit switches 174 and 176 are disposed within the path of the stem 158 of the actuator 148, whereby as the stem 158 is depressed the lowermost surface is brought into simultaneous operative engagement with the switches 174 and 176. These switches also are electrically coupled with a source of electrical potential, not shown, and upon operation are effective for simultaneously reversing the state of the relays 172 imposed through a simultaneous operation of the switches 168 and 170.

Since the T-bar 154 is adapted to be reciprocated in both horizontal and vertical directions, through an engagement therewith of a carton 18 as it is advanced into registration with the elevator 22, and as it is lowered by the elevator 22, the switches 168, 170, 174 and 176 are, in effect, cyclically actuated in response to predetermined, sequential positioning of the cartons 18 as a carton is advanced to the lidding station, elevated, lidded and lowered to again engage the upper surface of the roller 150 for thereby forcing the stem 154 downwardly.

Additionally, it has been found preferable to assure that a proper registration of a lid blank 14 is achieved prior to an activation of the elevator 22. Consequently, an additional normally-open limit switch 178, FIGS. 5 and 7, is interposed in circuit series between the switch 168 and an associated relay 172. This switch is adapted to be closed through an engagement therewith of a lid 14 and serves to assure that a circuit cannot be completed to the solenoid of the clutch 106 in the event a lid blank 14 is not present and properly registered on the lip 50. In the event that the switches 168 and 178 are closed, a carton 18 can be advanced upwardly between the plows 24 for down-folding the peripheral portions 25 of the lid blank 14 and thereafter positioning the peripheral portions of the lid 28 in an appropriate position relative to the staple guns 30 for purposes of securing the lids 28 to the cartons 18.

The staple guns 30, as a practical matter, are "ganged" and electrically interconnected for simultaneous operation. Consequently, the guns 30 can be controlled by employing any of several well established techniques. As illustrated in FIG. 7, it is preferred that each of the guns 30 be controlled through a solenoid operated, pneumatic valve 180. Each valve 180 is coupled within a fluid conduit and serves to deliver a pulsed flow of fluid, preferably oil, to an associated staple gun 30 for initiating its operation.

The valves 180 are electrically coupled with limit switches 182 and 184 mounted adjacent to one of the cams 90 which also functions as a control cam. The switch 184, preferably, is electrically coupled with all of the valves 180 and serves, upon closing, to initiate a simultaneous actuation of the guns 30 whereby at least eight staples simultaneously are driven into the lid 28 for thus securing the lid to its associated carton 18. However, the switch 182 is coupled only to the staple guns 30 aligned along the longitudinal axis of the conveyor 20. As a practical matter, the control cam 90 includes a switch actuator lobe 186 rigidly fixed to the cam at an appropriate angular location, relative to a 360.degree. cycle of operative rotation, so that the lobe 186 is caused to strike each of the limit switches during selected portions of a single cycle of operation of the cam.

Accordingly, the switch 184 is so positioned as to be engaged by the lobe 186 and effect a simultaneous actuation of all of the solenoid operated valves 180, for thus initiating a simultaneous operation of all eight of the staple guns 30, while the switch 184 is so positioned as to initiate operation of only four of the staple guns 30. As a practical matter, the lobe 186 is so situated as to close an electrical circuit through the switch 184 at the instant a carton 18 and its associated lid blank 14 has reached the uppermost limit of its elevation, and to engage the limit switch 182 during a dwell initiated by the stepped portion 96 of the surface of the control cam 90, to effect a second staple driving function for the staple guns 30 arranged along the longitudinal axis of the machine. The second staple driving function is achieved at opposite ends of the carton 18 so that each of the opposite ends of the carton includes four staples, while only two staples are applied to the opposite sides of the carton. Of course, any selected number of staples can be driven simply by providing for a repetitious operation of the guns 30.

OPERATION

It is believed that in view of the foregoing description, the operation of the device will be readily understood and it will be briefly reviewed at this point. It is to be understood that the carton lidding machine of the instant invention is disposed adjacent to a carton filling apparatus which serves to deposit selected contents within erected open-top cartons 18, prior to the cartons being delivered to the uppermost surface of the conveyor 20. Likewise, it is to be understood that the lid blanks 14 are caused to assume an appropriate orientation at the lidding station as they serially are fed between the bights 37 of the pair of feed rollers 34 and the pair of backup rollers 36 for thus positioning the lid blank 14 on the lip 50. As the lid blank 14 is caused to be registered, a closing of the limit switch 178 is effected whereby the control circuit for the elevator 22 is readied to respond to a closing of the switch 168.

The normally-closed switch 170 permits the drive train 66 to be driven in a continuous fashion for serially advancing the filled, open-top cartons 18 towards the lidding station 16. In a similar manner, the switch 168 normally is open to interrupt a circuit from the source of electrical potential to the solenoid of the clutch 106. Therefore, the elevator 22 initially is at its rest position beneath the level of the conveyor 20 as each carton 18, in turn, is advanced to the lidding station 16. However, as a carton 18 is advanced into an appropriate disposition beneath the registered lid blank 14, through an operation of the conveyor 20, the intercepting roller 150 is engaged by the leading end surface of the carton. In response to this engagement, the T-bar 154 of the actuator 148 is driven, against the bias of the associated spring 166, into simultaneous engagement with the switches 168 and 170, whereupon the solenoid of the clutch 62 is de-energized as a circuit is opened at one of the relays 172, of the pair of relays and the solenoid of the clutch 106 is energized, as a circuit is closed through the other relay 172, for thereby achieving a simultaneous deactivation of the drive train 58 and an activation of the drive train 98.

Due to the fact that the drive train 58 is de-activated, all horizontal displacement of the cartons 18 is arrested so that one of the cartons is disposed in predetermined registry with a lid blank now supported by the lips 50. Due to the fact that the drive train 98 is activated, the elevator 22 is advanced upwardly, as a rotation of the cams 90 is effected for thus causing the registered carton 18 to ascendingly advance into engagement with the lid blank 14.

Of course, the presser unit 110 is rendered effective for assuring a seating of the lid blank 14 relative to the carton 18 as the carton engages the blank. As elevation of the carton 18 continues, the presser unit 110 is elevated, while it continues to engage the blank, for thus maintaining a proper registry of the blank. Continued elevation causes the peripheral portions 25 of the lid blank 14 to engage the plows 24 and be down-folded about the lines 26 and to be brought into engagement with the vertical walls of the carton 18 to form a carton lid 28.

As the carton 18 reaches the upper limit of its upward advancement, the array of staple guns 30 simultaneously is activated, through a closing of the switch 184, for driving eight staples simultaneously into the down-turn peripheral portion of the lid 28. As the cam 90 continues to rotate, in response to the continuous operation of the drive train 98, a stepped lowering of the carton 18 is accomplished, as the stepped portion 96 of the periphery of the cams 90 is brought into engagement with the rollers 86. As the cams 90 continue to rotate, the lobe 186 engages the second limit switch 182 for causing the valves 180 associated therewith to function a second time for driving a second set of staples 29 at opposite ends of the carton.

Due to the configuration of the cam 90, each carton 18 raised by the elevator 22 remains substantially stationary for two dwell periods dictated by the configuration of the cam. However, once a stapling of the lid 28 to the vertical walls of the carton 18 being operated upon is completed, the cams 90 permit the elevator 22 to descend to its lowermost disposition whereupon the actuator 148, having been repositioned for locating the roller 150 at a point beneath the elevated carton, in response to the biased of the springs 166, is depressed for causing the stem 158 simultaneously to engaged the limit switches 174 and 176 which, acting through the relay switches 172, again cause the clutch 62 to become engaged and the clutch 106 to become disengaged whereupon the drive train 58 is activated and operation of the conveyor 20 is resumed, while the drive train 98 is deactivated and the operation of the elevator 22 is arrested. Once the drive train 58 is again actuated the conveyor 20 is driven for laterally advancing the lidded carton from the lidding station 16 to a discharge station, not shown.

In view of the foregoing, it should readily be apparent that the instant invention provides a practical and satisfactory solution to the problem of rapidly and efficiently lidding a series of open-top cartons in a manner which readily avoids overloading of the machine.

Although the invention has been herein shown and described in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of the invention, which is not to be limited to the illustrative details disclosed.

Claims

Having described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A carton lidding machine comprising: A. means defining a lidding station within said machine; B. a carton conveyor including means for vertically supporting and horizontally conveying an open-top carton through the lidding station; C. lid blank positioning mans for receiving and prepositioning a prescored lid blank of a substantially planar configuration in a vertical spaced relationship with said carton at said lidding station; D. elevating means for advancing said carton from a supported relationship with the conveyor along a linear path extending upwardly into lid-forming engagement with a prepositioned lid blank and for thereafter returning the carton into supported relationship with the conveyor; and E. lid securing means including a plurality of staple guns disposed in close proximity with said path for securing the lid to said carton prior to its being returned into a supported relationship with said conveyor.

2. The lidding machine of claim 1 wherein said conveyor comprises a pair of endless chains having coplanar reaches disposed in a side-by-side relationship, and said elevating means comprises a cam driven, vertically reciprocable table having a planar surface adapted to be advanced between the chains to engage the lower surfaces of the carton.

3. A carton lidding machine comprising: A. means including an intermittently driven endless conveyor for conveying open-top cartons through said machine; B. a lid applicator including means for receiving prescored lid blanks and positioning said blanks in a plane parallel with the plane of said conveyor; C. carton advancing means including an elevator for serially engaging cartons conveyed by said conveyor and elevating the cartons into a lid forming engagement with said lid blanks, and thereafter lowering the cartons and the lids into supported engagement with said conveyor; D. means for down-folding said lid blanks about the open top of said cartons as they are elevated; and E. a plurality of staple guns operatively associated with said lid positioning means for applying a plurality of staples to said lids for securing the lids to said cartons.

4. The machine of claim 3 further including control means coupled with said staple guns for initiating operation of said guns.

5. The machine of claim 4 wherein the carton advancing means includes means for lowering the cartons in incremental steps and said control means includes means for initiating operation of the staple guns during dwells between said steps.

6. In a carton lidding machine for use in lidding open-top cartons, the combination comprising: A. means defining a lidding station including support means for receiving and supporting in a substantially horizontal plane a prescored lid blank of a substantially planar configuration; B. lid blank feeding means for delivering prescored lid blanks to said support means; C. a carton elevator disposed beneath the support means for receiving an open-top carton; D. drive means for imparting rectilinear motion to said elevator for upwardly displacing said carton along a linear path and into engagement with a lid blank delivered to said support means and for thereafter lowering said carton along said path; E. means including a plurality of plows disposed adjacent to said path for engaging said lid blank and down-folding the peripheral portions thereof about the top of the open-top carton as said carton is displaced upwardly; and F. means including an array of staple guns operatively associated with said station in close proximity with said path for stapling the down-folded peripheral portions of the lid blank to said carton.

7. In the machine of claim 6, the combination further comprising means including a horizontally extended carton conveyor operatively associated with said lidding station for horizontally advancing said open-top carton to and from said carton elevator.

8. The combination of claim 7 wherein said conveyor comprises an intermittently operated horizontally disposed endless conveyor extended through said lidding station.

9. The combination of claim 8 wherein said elevator comprises a vertically reciprocable table.

10. A carton lidding machine comprising: A. a horizontally disposed, intermittently operable endless conveyor having a horizontally extended reach for receiving and horizontally advancing open-top cartons in stepped advancement through said machine; B. a carton lidding station disposed between opposite ends of the conveyor having a vertically reciprocable elevator having, 1. means including a table configured to be reciprocated in vertical directions relative to said conveyor for engaging horizontally advanced, open-top cartons, 2. means including a plurality of rotatable cams, each having an irregular surface and supported for rotation about an eccentric axis, for elevating said table above said conveyor in a continuous motion and thereafter lowering the table in incremental steps, 3. lid forming means for deforming lid blanks about the open-top cartons as the table is elevated, and 4. lid securing means for securing the lid blanks to the cartons as the table is lowered; and C. control means for imposing a sequential mode of operation on said machine.

11. The machine of claim 10 wherein said control means includes a plurality of limit switches operatively associated with said conveyor and said elevator, adapted to respond to the presence of an open-top carton at said lidding station for interrupting the operation of the conveyor and initiating advancement of said elevator.

12. The machine of claim 10, wherein said securing means includes a plurality of pneumatically actuated staple guns, adapted to be actuated in a predetermined sequence.