US2977861A

US2977861A - Carton making machine

Info

Publication number: US2977861A
Application number: US736600A
Authority: US
Inventors: Alex S Gibb
Original assignee: Continental Can Co Inc
Current assignee: Continental Can Co Inc
Priority date: 1958-05-20
Filing date: 1958-05-20
Publication date: 1961-04-04
Anticipated expiration: 1978-04-04

Description

April 4, 1961 A. s. GIBB CARTON MAKING MACHINE 7 Sheets-Sheet 1 Filed May 20, 1958 ATTORNEYS R m m V m April 4, 1961 A. s. GIBB CARTON MAKING MACHINE 7 Sheets-Sheet 2 Filed May 20, 1958 INVENTOR (ribb 9 1 f 7 2/ MN 9 1 a 2 2 g n m? m 2 l w I II 7 v u" m m 6 5 9 3 a J MW 2 3 2. MA. 2 7

Alex (-5:

BY W, M 8 ATTORNEY-5 April 4, 1961 A. s. GIBB 2,977,861

CARTON MAKING MACHINE Filed May 20, 1958 7 Sheets-Sheet 3 ATTORNEYS @242, Jam in April 4, 1961 A. s. GIBB 2,977,861

CARTON MAKING MACHINE Filed May 20 1958 7 Sheets-Sheet 4 M 7a 73 l ll l i 68 68 i 6'2 I 75: 70] 62 Alex cf. 52155. //mZ,fl J Mp ATTORNEYS April 4, 1961 A. S. GIBB CARTON MAKING MACHINE Filed May 20, 1958 7 Sheets-Sheet 5 2 T E i Ja g H 1 65 'l I I 'L' J] .5] L E

INVENTOR

6,62 J5 g3 ijl ex 523$.

BY 6w, wj xzw ATTORNEYS April 4, 1961 A. s. GIBB CARTON MAKING MACHINE 7 Sheets-Sheet 6 Filed May 20, 1958 INVENTOR A Z Ex 6f 6'2 bi Q MH QNW Nu MWMWW ORNEY April 4, 1961 A. s. GIBB 2,977,861

' CARTON MAKING MACHINE Filed May 20, 1958 7 Sheets-Sheet 7 INVENTOR 56 426.15 :5? z'ifi.

Ma ina, w /dflugm ATTORNEYS United States Patent 2,977,861 CARTON MAKING MACHINE Alex S. Gibb, Bradenton, Fla., assignor to Continental Can Company, Inc, New York, N.Y., a corporation of New York Filed May 20, 1958, Ser. No. 736,600

18 Claims. (Cl. 93-51) This invention relates to machines for use in the manufacture of cartons from cardboard, fiber board and the like, and is similar to the machine disclosed in the U.S. patent application of Alex S. Gibb, Serial No. 630,938, filed December 27, 1956, now US. Patent No. 2,896,518, granted July 28, 1959.

In both machines, the cartons are formed frompre cut blanks, each having a rectangular body, side flaps joined along fold lines to the longitudinal edges of said body, end flaps'joined along fold lines to the end edges of said body, and corner flaps joined along fold lines to the ends of said side flaps. The blanks are successively are first operated t-oupwardly fold the corner flaps from the side flaps. The side flap folders are next operated to upwardly fold the side flaps against the sides of the plunger and to thereby swing the upwardly folded corner flaps inwardly to positions at the ends of the plunger. Then the plunger is operated to depress the partly conipleted carton into thethroat frame, and this causes upthe plunger is longitudinally expanded toxtightly press the end and corner flaps together for good union between ward swinging of the adhesive-carrying end flaps against the corner flaps. While the carton is in thisthroat frame,

them, and the plungeris then contracted and raised, 75;

leaving thecarton in thethroat frame to be pushed downwardly by'the next formed carton and eventually conveyed from the machine. The dwell of the carton before conveyance from the machine allows tim'efor the 'Figure 11 is a transverse vertical section on line 11-11 adhesive to setv The machine of the above identifiedmapplication was rapid and efficientbut was restricted to the manufacture machine for the manufacture of cartons of-various sizes and thusexpanding the field of use of the machine,- 1

" 'presentinvention, however, has aimed to provide a new and improved construction permitting adjustment of the iii-'43 of Figure 12.

tively shallow cartons; and a further object has been to provide a novel construction for elfecting plunger descent to any required extent and for then stopping the descent, the stop means being quickly and easily adjustable as required.

The production of cartons of different sizes requires that the Size of the plunger be readily changeable; and another object has been to make novel and advantageous provision for fulfilling this requirement.

A still further object has been to provide novel means for holding the inturned corner flaps against the ends of the plunger prior to upward folding of the end flaps, said means, however, being movable out of the paths of said end flaps as the latter are folded against said inturned corner flaps. 7

With the above and other objects in view that will hereinafter appear, the nature of the invention .will be more clearly understood by reference to the following detailed description, the appended claims and the several views illustrated in the accompanying drawings.

In the drawings: l 7 V Figure 1 is a perspective view diagrammatically show ing a magazine for theblanks, one blank fed from said magazine to a glue-applying station, and another blank advanced to the carton-forming station.

Figure 2 is a diagram showing the corner flaps of the blank folded upwardly from the side flaps.

Figure 3 is a diagram showing the side flaps of the blank folded upwardly and the corner flaps consequently swung inwardly.

Figure 4 is a diagram showing the partly completed carton of Figure 3 entering the throat frame and theend flaps consequently moving upwardly and inwardly for contact with the corner flaps. j

Figure 5 is a' perspective view of one of the completed cartons. V I

Figure 6 is'an end'view showing the construction at the carton-forming station. See the arrow f Figure 8. Figure 7 is an enlarged horizontal sectional view on line 77 of Figures 6 and 8, partly broken away.

Figure 8 is a View partly. in verticalsection substantially on line 8-8 of Figure 7, and partly inelevation as indicated by the-arrow 8 of Figure 6.

Figure-9 is an enlarged vertical longitudinal section through the upper part of the machine, as indicated by line 9'-9 .of Figure 6, but showing the plunger in a lower position. r Figure 10 is a similarly enlarged vertical longitudinal section th rough thelower portion of the machine online Ill-[10 of Figures 6 and 7'.

of Figures 7 and 10.

Figure 9. e Figure 13 is a vertical jiFigure 14 is a vertical transverse section on line M ld of FigurelZ.

in carrying ont theabove end, a f rther object has been to construct the throat frame from'independent side and end members inwardly and outwai'dlyshiftable to varythe size of said. throat frame; and to mount the corner flap folders. on said end members for shifting bodily therewith. Thus, when the side and eiid IIlBITl-f adjustment.

j The production of "relativelyfdeep cartons requires n that theiplungergclescenda greater-tlistanc'efthan orrela- The features of novelty sh own in detail in the drawing are all embodied in the' end or the machinezpositionallyddentified as -Carton-Forming stationiin "Figure 1. However, as the carton blanks Bi are to be me- I chanically fed from a suitable blank magazine to aiglueapplying station "and each glued blankfis to. bejthen' advanced to the forming station, the blank magazine and glue-applying. stations have also been diagrammatically shown i n,Figure-1. In this same view a blank feeding means M is diagrammatically illustrated as operable a pneumatic.cylinder-and-pistcnassemblyA. T he feedsing means M has been illustrated as-having feed dogs F f forfeedingtm blanks B one at'a time tothe glue-apply f longitudinal section Lon line Each blank B comprises a rectangular body B two side flaps B joined along fold lines to the longitudinal edges of said body B two end flaps B joined along fold lines to the end edges of said body B and four corner flaps B joined along fold lines to the ends of the side flaps B respectively.

The required glue G is applied to the end areas of the end flaps B at the glue-applying station and the glued blank is then advanced to the forming station. At this station, the corner fiaps B overlie folders 2t) and the side flaps B overlie folders 21. The corner fiaps B are first folded upwardly to vertical positions as shown in Figure 2, by means of the corner flap folders 20. Then by means of the side flap folders 21, the side flaps B are upwardly folded as shown in Figure 3. This movement inwardly swings the corner flaps B to positions at the ends of the body B in readiness for upward folding of the end flaps B Prior to this latter operation, the folders 20 return to normal positions, but outward springing of the corner flaps B is then prevented by flap holding bars 22 shown in Figure 3. partial folding of the blank as so far described, it is depressed by a plunger 23 into a rectangular throat frame 24 as shown in Figure 4, to thereby cause upward foldingof the pre-glued end flaps B against the corner flaps B. As soon as the end flaps B have started upwardly, the bars 22 are moved to out-of-the-way positions and the continued depression of the plunger 23 completes the upward folding of the end flaps B against the corner flaps B Then, the plunger 23 expands longitudinally to press the end and corner flaps tightly together to cause the glue to firmly bond them to each other. The plunger 23 then contracts and ascends to its normally raised position and the next glued blank is advanced between said plunger 23 and the throat frame '24. As the folding of this next blank is completed by depression into the throat frame 24, it downwardly moves the previously shaped carton and so on. The completed cartons C (Figure successively leave the throat frame 24 and are conveyed away from the machine. In the meantime, the dwell of each carton Cin the throat frame 24 has been suflicient to allow setting of the glue which secures the flaps B? and B together.

Strictly speaking, the plunger 23, throat frame 24- and After ed by this throat frame communicates with the plate opening 31.

Th roar frame The throat frame 24 is shown in Figures 6 to 11 and comprises two side members 33 and two end members 34 each of which has a base 35 slidably inset in the top of the plate 30, a wall 36 rising from the inner edge of the base 35, and two end webs 37. Screw-and-slot connections 38 secure all of the bases 35 to the plate 30 and, when loosened, permit inward or outward shifting of the side and

end members

33 and 34 according to the size of the cartons to be produced. Screws 39 are provided for shifting the side and

end members

33 and 34 when the connections 38 are loosened. Each of these side and

end members

33 and 34 is provided with a central downwardly projecting flap holding plate 40 which extends through the plate opening 31 and is flush with the inner side of the wall 36. Each plate 40 has a reinforcing rib 41 and the four ribs are received respectively in the four notches 32 in the side and edge walls of the opening 31.

The element 24a in Figures 7, 10 and 11 is simply a stripper to prevent possible ascent of a completed carton with the plunger 23.

Corner flap folders The corner flap folders 20 are shown in Figures 6 to 11 and they are pivotally mounted on brackets 42 secured to the end webs 37 of the two throat frame end members 34. Pneumatic cylinder and piston assemblies 43 are also pivotally mounted on the end webs 37 of the end members 34 and are connected with the corner flap folders 20 for operating them. Inward or outward shifting of the end members 34, according to the length of the cartons to be produced, also shifts the corner flaps 20 and their operating means to the required new positions without requiring independent adjustment.

Side flap folders The side flap folders 21 are shown in Figures 6 to 11 and they are pivotally mounted in bearings 44 secured to the walls 36 of the two throat frame side members 33. Pneumatic cylinder and piston assemblies 45 are mounted on the bases 35 of the side member 33 and are connected with the side flap folders 21 for operating them.

flap holding bars 22 would appear in all of Figures'l to 4, but the disclosure has been simplified by showing these elements only in the views depicting their functions.

General frame structure Theframe structureiof the machine is shown principally in Figures 6 to 11. Two longitudinal .side bars 25 are supported by legs 26; and two transverse" arched frames 27 have their lower ends secured upon said side 30 supports the throat frame 24 and the spacesttrroundv length.

Inward or outward shifting of the side members, according to the width of the cartons to be produced, also shifts the side flap folders and their operating means to the required new positions without requiring independent adjustments.

Plunger construction The plunger 23 while shown on a small scale in Figures 6 and 8, is illustrated in detail in Figures 9 and 12 to 14. This plunger has a bottom plate 46, two side walls 47 detachably secured at 48 (Figure 14) to said bottom plate 46, and two projcctable and retractable end walls 49. These end walls 49 have guide wings 56 slidably'engaged with guidesSl on the side walls 4-7. These side walls are tied together at their upper edges by transverse tie bars 52 which are detachably secured at 53 thereto. By removing the side walls 47 and substituting thicker walls, to project laterally beyond the bottom plate 46, the width of the plunger 23 may be increased for the production of wider cartons, the side plates 47 herein shown being intended for use when cartons of minimum width are-to be produced.

Provision is also made for va ying the length of the plunger 23 for the production of cartons of a different Two aligned guides 54 are secured upon the bottom plate 46 near its ends; and two aligned horizontal stop bars 55 are. slidably and ncn-rotatably mounted in said guides 54. The outer'ends of the bars 55 have T-heads' 56to abut the endwalls 49 limitthe'irn means for limiting" I {explained below;

aev'nser ward movement of these end walls. The inner ends of the bars 55 are connected by a turnbuckle 57 which may be held against longitudinal shifting in any preferred way, for example, by the forked plate 58 shown in Figure 12. By rotating the turnbuckle 57 in the required direction the stop bars 55 may be adjusted to efiect lengthening or shortening of the plunger 23 according to the length of the cartons to be produced.

It will be recalled that after the folded carton blank has been completely depressed into the throat frame 24 by the plunger 23, this plunger is to be longitudinally extended to press the corner flaps B tightly against the end flaps B This is accomplished by outwardly projecting the plunger end walls 49; and for this purpose pneumatic cylinder and piston assemblies 59 are provided. The cylinders of these assemblies are secured upon the bottom plate 46 and the piston rods are secured to the end Walls 49. Springs are-preferably provided to retract the end Walls 49 to allow ascent of the lowered plunger; and one of these springs is shown at 60 in-Figure 13. When these springs are permitted to act, upon exhaust of air from the cylinders of the assemblies 59, the inward movement of the end walls 49 is limited by the positions to which the stop bars 55 have been adjusted.

The height of the plunger 23 is determined according to maximum depth of the cartons to be produced. However, for relatively shallow'cartons, the plunger is not depressed as far as for deeper cartons. This is taken care of as explained below.

; Plunger operating and stroke varying m ieans 7 Pneumatic cylinder and piston assemblies 66 have their cylinders 67 secured to and projecting downwardly from the plate 28, in "inwardly spaced parallelrelation with the rods- 62. Thejpistonirods 68of'the assemblies 66 have upwardly projecting portions secured tothe yoke crown bar 64 and downwardly projecting portions secured-to the guides ,54jof the plunger 23. Thus, the assemblies 66: are operable required; r p

' As-the' ascent of the plunger 23 is always the'sarne, regardlessbf the depth of the cartons being produced, fixed stops 69 may be'provided on the lower-ends of the piston mares to'strike the lower ends of .the cylinders 67 and limit said ascent. However, ,as the plunger should descend a relatively short distance for shallow cartons and a. greater distance for deeper cartons, the

v i Two "externally threaded tubular -guides7Q," faithspiston rodsf6 are secured at 71. upon the, plate 28. Two stoptsleeves 72 are threaded upon theguides. 70; and two stops'73 are secured 'to thelyoke 61 ortothe rods 63K- the plunger descent s adjustable'as 6 tionally adjusted as required. Friction may be relied upon to hold the gear 74 against accidental turning, or positive locking means may be employed.

Corner flap holders The mounting and operating means for the corner flap holding bars 22 are shown in Figures 6, 8 and 9. One bracket 76 is secured to and projects downwardly from each end of the plate 28; a second bracket 77 is secured for vertical adjustment to said one bracket 76; a third bracket 73 is secured for horizontal adjustment to said second bracket 77; and the direction of adjustment of said third-bracket 78 is longitudinally of the machine. The corner flap holding bars 22 are below the brackets just described but are secured respectively, to the lower ends of vertical arms 79, the upper ends of whichare pivoted at till to the brackets 78, respectively, the pivots 86 being at right angles to the line of adjustment of said brackets 78 to allow swinging of said arms 79 toward and from the ends 49 of the plunger 23. Two hand levers 31 are fulcrumed at 82 to the two brackets 78,

respectively, the fulcrums 32 being inwardly and downwardly spaced from the arm pivots 80 and being parallel .to'jdepress andraise the plunger 23 as i therewith. A link 83 connects each lever 81 with the associated arm79, said link being provided at 84 to said lever 81 and at 85 to said arm 79. Normally, each of the hand levers 81 occupies a lowered horizontal position as depicted at the left of Figure, 9 and the corner flap holding bar 22 is then in cooperative relation with the plunger end 49. At this time, thelink pivots 84 and 85 and the lever fulcrum 82 are on dead center and a stop arm 86 on the link 83 abuts the arm 79 to prevent further downward movement of the hand lever 81. Accidental upward movement of the lever 81 is prevented by the weight of its free end. Consequently, each corner flap holding bar 22 is stationarily'held in spaced cooperative relation with the plunger end 49 to permit entrance of the corner flaps B between said bar 22 and plunger end 49 when said corner flaps B are moved from the positions of Figure 2 to those ofFigure 3. However, as the plunger 23 initiallydescends and starts to cause upward folding. of the end flaps E (Figure 4), the bars 22 remain stationary and slide ofi of the corner flaps B as the end flaps B move into contact with the corner flaps E the end flaps B clearing the bars 22.

Under certain conditions a corner flap B will jam between one of the bars 22 anda plunger end when the corner flaps are swung from their positions, of Figure 2 to their positions of Figure 3. When this occurs, the

Two flangedtrack bars 87 (Figures .6, ,7, a, 10 and 11) are provided to support and guide each body blank B as size ofthe cartons tobe produced. Both ends of these to strike'the upper ends of said 'stop' s1eeves172 to limit descent of the plunger '23.

required;

"The two stop sleeves 72 areso connected that they" canbie adju'sted only in' unison. As an adequate 'con-,

, it'is' fed to the forming station into position between the throat frame 24 and 'the normally raised plunger 23. Thesejtrack bars 87 are. adjustable inwardly and outwardly .for blanks of one .width or another, according to the track bars 87 may be mounted and adjusted in substan -t ially the same way but the mounting and adjusting meansis shown for only one end of said track bars. These bars are provided with downwardly projecting blocks 88 'slidably engaged with a fixed transverse. track bar39, theen'ds' offwhich have supports 90 securedupon nesting means, a gear 74 is mounted onthe plate lb-between the stop'sleeves 72 and these sleeves are;

provided with elongated gear teeth meshingtwith the teeth of said gear 74; By turning this'ge'a'r 74 hrone H v p 7 V f direction orthe other the stop sleeves'lZ may be-posi- '75 justing screws, tor the opposite ends of the track bars the mainframe side bars 25.v A transverse adjusting screw 91 is rotatably supported bythesupports 9i and 1 is threaded throughthe blocks" 88 with5a right hand I,- .thread'forone blockand a left hand thread for the other "block." Thus, lily-simultaneously rotating the two adl 87, in the same direction, said track bars may be adjusted inwardly or outwardly as required. The two screws are connected for simultaneous rotating, by a chain and sprockets. One of these sprockets is shown at 92 in Figures 6 and 7, and part of the chain is shown at 93 in Figure 7. Either screw may have a suitable hand wheel or crank for rotating it.

Machine activating switch A switch 94 (Figures 6 and 8) is provided, to be closed by the blank B when said blank reaches its final position at the forming station, to activate the machine and produce a carton. This switch is mounted on a bracket bar 95 which is adjustable along brackets 96 secured to one of the throat frame end members 34. The switch 94 may thus be adjusted positionally according to the length of the blanks being handled by the machine.

Pneumatic system The various cylinder and piston assemblies A (for the blank feeding means M of Figure 1), 43 (for the cornerfiap folders 45 (for the side flap folders 21), 59 (for the plunger ends 49), and 66 (for the plunger 23), have suitable compressed air lines connected thereto and these lines have electrically operated air admission and exhaust valves. These valves are controlled by a timer driven by an electric motor which is started by the switch 94. Whenever this switch is closed by the blank B, the timer makes one revolution and during said revolution (the various cylinder and piston assemblies function to cause operation of the feed means, flap folders and plunger in proper sequence.

As a good example of such a system is given in the patent application above referred to, the present case need not be encumbered by illustration and specific description.

Operation As the foregoing explanation under the heading Prologue gives a good understanding, redundance is avoided by not here recapitulating.

While the various features of the invention have been herein rather specifically described, it is to be understood that variations may well be made within the scope of the invention as claimed.

I claim:

1. In a machine for constructing a carton from a blank having a rectangular body, side and end flaps joined to said body, and corner flaps joined to said side flaps; a vertically fixed rectangular open throat frame to underlie said body, said throat frame having'shiftably mounted upstanding side members adjustable inwardly and outwardly according to the width of said body, said throat frame also having shiftably mounted upstanding end members adjustable inwardly and outwardly according to the length of said body, means for securingsaid side and end members in fixed operational positions after positional adjustment-thereof, corner flap folders hingedly mouutedon the ends of said end members and shiftable bodily with these end members when positionally adjusting the same, said corner flap folders being operable to fold said corner flaps upwardly from said side flaps, side flap folders hingedly mounted on said side members and shiftable bodily with these side members when positionally adjusting the same,. said sidefiaphaving means whereby its size may be jvaried according i to the sizeof the blank body. e

3. A structure as specified in claim 1, in which said side and end members are provided with downwardly projecting flap-engaging plates shiftable bodily with said side and end members when positionally adjusting these side and end members, said flap-engaging plates being flush with the inner sides of said side and end members.

4. A structure as specified in claim 1, in which said corner flap folders are provided with cylinder and piston assemblies for actuating them, said assemblies being mounted on the ends of said end members to shift bodily with these end members when positionally adjusting the same.

5. A structure as specified in claim 1, in which said side flap folders are provided with cylinder and piston assemblies for actuating them, said assemblies being mounted on said side members to shift bodily with these side members when positionally adjusting the same.

6. A structure as specified in claim 1, in which said corner flap folders are provided with cylinder and piston assemblies for actuating them, said assemblies being mounted on the ends of said end members to shift bodily with these end members when positionally adjusting the same, said side flap folders being also provided with cylinder and piston assemblies for actuating them, these assemblies being mounted on said side members to shift bodily with these side members when positionally adjusting the same.

7. A structure as specified in claim 1; in which a fixed horizontal supporting plate is provided for said side and end members said plate having an opening through which the carton is depressed by said plunger, said side, and end members each having a horizontal base resting on said supporting plate and a vertical wall integral with and rising from the inner edge of said base, each of said end members also having end webs integral with its base and plate, said corner flap folders and side flap folders having cylinder and piston assemblies for actuating the same, the cylinder and piston assemblies for said corner flap folders being mounted on the aforesaid end webs of said end members, the cylinder and piston assemblies for said side flap folders being mounted on the bases of said side members.

8. In a carton forming machine having a throat frame into which a partly folded carton blank is to be depressed to complete folding of said-blank; a plunger to overlie the blank body, a fixed horizontal cylinder supportmounted above said plunger, a yoke secured to and rising from said plunger, said yoke having a crown bar above said fixed cylinder support, two cylinder and piston assemblies for actuating said plunger, the cylinders of said assemblies being secured to and projecting downwardly from said cylinder support, said assemblies having piston rods projecting upwardly from said cylinders and secured at their upper ends to said crown bar of said yoke, two stops mounted on saidcylinder support for vertical adjustment, said stops being disposed adjacent said piston rods respectively and being effective to limitzdescent of said plunger andyoke in accordance with the height of carton being formed, and connecting means between said two stops for insuring simultaneous adjustment thereof.

9'. In a carton forming machine having a throat frame into which a partly folded carton blank is to be depressed to completefolding of said blank; aplunger to overlie .the blank body, a fixed horizontal cylinder support mountprojecting upwardly from said cylinders and secured at their upper ends to said crown bar of said yoke, two vertical tubular guides through which said piston rods extend slidably, the lowerends of said'tubular guides being set cured to said cylinder support, the upper end of said tubular guides being downwardly spaced from the aforesaid crown bar of said yoke, two stop sleeves threaded for vertical adjustment on said two tubular guides respectively, said stop sleeves being effective to limit descent of said yoke and plunger in accordance with the height of cartonbeing formed, and connecting means between said two stop sleeves for insuring simultaneous adjustment thereof.

10. A structure as specified in claim 9, in which said stop sleeves are provided with external vertically elongated gear teeth and in which a gear is mounted on the aforesaid cylinder support, the teeth of said gear being in'mesh with the teeth of said stop sleeves, whereby rotation of said gear will rotate both of said-stop sleeves to vertically adjust them in unison.

11. In a carton forming machine having a throat frame into'which a partly folded carton blank is to be depressed to complete folding of said blank; a plunger to overlie the blank body, a fixed horizontal cylinder support mounted above said plunger, two cylinder and piston assemblies for actuating said plunger, said assemblies including cylinders secured to and projecting downwardly from said cylinder support and piston rods projecting both upwardly and downwardly from said cylinders, the lower ends of said piston rods being secured to said plunger, two stops mounted for vertical adjustmenton said cylinder support and located adjacent the upwardly projecting portions of said piston rods respectively, stop means above the aforesaid two stops. andmovable bodily with said piston rods, said two stops being in the downward paths of 7 said stop means to limit descent of said piston rods and plunger in accordance with the height of carton being formed, and connecting means between said two stops for insuring adjustment thereof in unison.

12. In a carton forming machine having a throat frame into which a partly folded carton blank is to be depressed to complete folding of said blank; a plunger to overlie the blank body, a fixed horizontal cylinder support mounted above said plunger, two cylinder and piston assemblies foractuating said plunger said assemblies including cylinders secured to and projecting downwardly from said said plunger having side walls secured to said bottom plate and against which to upwardly fold side flaps of the carton blank, said plunger also having projectable and retractable end walls against which to upwardly fold end' flaps of the blank, means for projecting and retracting said end Walls while said plunger is within a folded blank, two aligned stop bars slidably mounted on said bottom plate and having their outer ends disposed to limit the retraction of said end walls, and a turnbuckle connecting the inner ends of said stop bars for simultaneously adjusting them outwardly or inwardly according to the length of the blank body.

16. In a machine for forming a carton from a carton blank having a body, side and end flaps connected to said body, and corner flaps connected to said side flaps, said machine having a plunger against which to upwardly fold said side flaps after first upwardly folding said corner flaps, whereby said corner flaps will occupy positions at the ends of said plunger when said side flaps are upwardly folded and the blank will thus be in readiness for upward folding of said end flaps against said corner flaps, corner flap holding members spaced outwardly of said plunger ends to abut and temporarily hold said corner flaps at said plunger ends, means mounting said corner flap holding members for outward shifting, the mounting means for each of said corner flap holding members including an arm carrying the holding member, a fixed bracket to which the upper end of said arm is pivoted, a verticallyswingable hand lever fulcrumed at one end to said bracket, a link pivoted to both said arm and said bracket for outwardly swinging said arm as said lever is upwardly moved and vice versa, and means for limiting cylinder support and piston rods projecting both upwardly movable bodily with said piston rods, said two stop sleeves being in the downwardpaths of said stop means to limit descent of said piston rods and plunger in accordance and downwardly from'said cylinders, the lowerends of said piston rods being sef'cured to said plunger, two

with the height of carton being formed, and connecting,

means between said two stop sleeves for insuring adjust-i ment thereof in unison.

-13. A structure as specified in claim 12, in which said I stop sleeves are provided with "external vertically elongated gear teeth and in which, a gear is mounted on the to vertically adjust them in unison.

14. In a carton forming machine, a plunger to overlie the body ofa carton blank, said plunger havingside walls against which toupwardl'y fold sidefiaps of the blank, said plunger also having projectable and retractable end walls against which to upwardly fold end flaps of the blank, means for projecting and retracting said end walls while,

said plunger is within a folded blank, two adjustably mounted stops the inward paths of said :end walls re spectively for limiting'the retraction of these, end walls,

and connecting means between said stops for insuring a simultaneous adjustment thereof.

In a carton" forming machine, a plunger having which the lever fulcrum and the link pivots are on or past dead center to then stationarily hold said arm and the flap holding member carried thereby.

17. In a carton forming machine having a throat frame into which a partially folded carton blank is to be depressed to complete folding of said blank; a plunger to overlie the body blank, a fixed horizontal cylinder support mounted above said plunger, a yoke secured to and rising from outer portions of said plunger, said yoke having a crown bar above said fixed cylinder support, two cylinder and piston assemblies for actuating sa'id plunger, the cylinders of said assemblies being secured to and projecting downwardly from said cylinder support, said cylinders having pistonrods extending up- Y wardly and downwardly from saidcylinders, said piston rods having their upper ends secured to said crown bar and their lower ends secured to said plunger inwardly of the connections between said yoke and said plunger to provide for the stable supporting of said plunger.

18. In a carton forming machine having a throat frame into which a partially folded carton blank is to be depressed to complete folding of said blank; a plunger to overlie the body blank, a fixed horizontal cylinder sup.-

port mounted above said plunger, a yoke secured'to and. rising'from' outer portions of said plunger, said yoke having-a crown bar above said ffixed cylinder supportfltwo cylinder andpistou assemblies for actuating said plunger, the cylinders of said assemblies being secured to and projecting downwardly from saidcylinder support; said cylinders having piston rods extending upwardly and downwardly from said cylinders, said piston rods having their upper ends securedto said crown bar andltheir lower ends secured to said plunger inwardly of the con nections between said yoke and saidplunger to provide for the stable supporting of said plunger, and stop means mounted for vertical adjustment on said cylinder support and effective to limit descent of said .yoke andsaid plunger in accordance withthe height ofjcarton being I formed.

(References oh following page) v References Cited in the file of this patent UNITED STATES PATENTS Diskin Nov. 23, 1926 12 Hickin Sept. 2, 1952 Gannon et al. Oct. 27, 1953 Bell et a1 Feb. 14, 1956 Clement July 9, 1957 Plough et al. Jan. 21, 1958 Hickin et a1 Apr. 15, 1958 Gschwind et al. Aug. 26, 1958