US3391618A

US3391618A - Corrugated carton blank folding machinery

Info

Publication number: US3391618A
Application number: US523347A
Authority: US
Inventors: Everett W Clem
Original assignee: SPECIALTY EQUIPMENT CORP
Current assignee: SPECIALTY EQUIPMENT CORP
Priority date: 1966-01-27
Filing date: 1966-01-27
Publication date: 1968-07-09
Anticipated expiration: 1985-07-09

Description

July 9, 1968 E. w. cLEM 3.391.613

CORRUGATED CARTON BLANK FOLDING MACHINERY v 7 sheets-smet 1 Filed S .GE

7 Sheets-Sheet 2V m .s m w. Ww n A A 1m ,yA \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\mw. ww. m W JM.

E. w. CLEM CORRUGATED CARTON BLANK FOLDING MACHINERY July 9. 1968 Flled Jan. 27, 195s July 9, 1968 E. w. CLEM CORRUGATED CARTON BLANK FOLDING MACHINERY Filed Jan. 27, 1966 '7 Sheets-Sheet l5` mn I INVENTOR EVERETT W CILEM WH.. L W.,

` ATTORN EYS '7 Sheets-Sheet 4 EVERE TT W. CLEM n gianna; s

July 9, 1968 E. w. cLEM CORRUGATED CARTON BLANK FOLDING MACHINERY 7 Sheets-Sheet 5 Filed Jan. 27, 1966 FIG. 8

INVENTOR.'

EVERETT w. CLEM `|7 A d E ATTORNEY;

July 9. 1968 E. W. CLEM 3,391,618

CORRUGATED CARTON BLANK FOLDING MACHINERY Filed Jan. 27, 1966 7 Sheets-Sheet 6 FIG. 9

INVENTOR. EVERETT W. CLEM TORNE'YS E. W CLEM CORRUGATED CARTON BLANK FOLDING MACHINERY Filed Jan. 27, 1966 July 9. 1968 e wn n Nw ATTORNEYS United States Patent Oft-ice 3,391,618 Patented July 9, 1968 3,391,618 CORRUGATED CARTON BLANK FULDING MACHINERY Everett W. Clem, Shrewsbury, Mass., assignor to Specialty Equipment Corporation, Westboro, Mass., a corporation of Massachusetts Filed Jan. 27, 1966, Ser. No. 523,347 19 Claims. (Cl. 93-52) ABSTRACT OF THE DISCLOSURE The present invention is directed to apparatus intended for `use in conjunction with high speed corrugated box blank folding equipment for establishing accurate alignment of folded-over panels of carton blanks preparatory to and during the completion of the manufacturers joint. The apparatus of the invention includes special folding sword mechanisms for improving the efficacy of a folding machine during the final stages of folding of the outer carton blank panels. Additionally, the apparatus of the invention includes special longitudinally extending guide belts adapted to establish gradually and gently the predetermined gap between the opposed edges of the foldedover panels and to maintain the gap and the alignment of the panels for the subsequent completion of the manufacturers joint.

The present invention relates to improvements in apparatus employed for automatically folding corrugated carton blanks into collapsed tubes suitable for subsequent squaring and formation into cartons.

In the evolution of corrugated cartons, the blanks from which they are formed have assumed a variety of shapes and sizes, which are formed into collapsed multiwalled tubes by gluing, stitching, stapling, or taping operations. High speed machines for automatically folding these carton blanks have been available to the art and many of these machines, including a carton folding machine described and illustrated in copending application Ser. No. 224,951, led Sept. 20, 1962, now U.S. Patent No. 3,270,628, issued Sept. 6, 1966, employ conveying apparatus to engage the inner panel portions of a flat carton blank and to transport the blank through the machine along a straight path. Typically, as the blank traverses the machine, its outer panel portions (one of which may include a glue flap) are continuously and progressively engaged and folded through 180 and over the inner panel portions by appropriate folding apparatus. After the outer panel portions have been flat-folded, a -manufacturers joint is formed, and the tube is completed by taping or otherwise connecting the overfolded panels, such as, for example, by pressing together a flatfolded glue 'Ilap and underlying panel portion.

Many of the new blanks required to be handled by machinery are asymmetrical and/or elongated in configuration. This asymmetry or elongation often introduces severe difficulties in handling and folding the blanks, which may cause incorrect taping or gluing of the joints of the tube, jamming of the folding machine, and other associated problems when the blanks are run through conventional blank folding machinery.

When handling asymmetrical and/ or unusually shaped blanks which are to be taped or glued, it is important to establish and to maintain a uniform spacing or a uuiform gap between the opposing carton edges which are to be taped or glued. Thus, as an important aspect of the present invention, novel and improved arrangements are provided in a folder-gluer, folder-taper or like blank handling apparatus to establish and to maintain accurate control over the gap at the secured edges forming the manufacturer-s joint of the carton tube.

lof the gap with the path of the blank may be readily appreciated when the consequences of taping a nonalgned or non-parallel blank are considered. The tape, which is laid down parallel to the straight path of the blank, will intersect a portion of the gap leaving the remainder of the gap untaped. A carton erected from such a tube will 4have an incomplete joint and will be unacceptable. Furthermore, an improperly taped blank cannot be manually squared after the tape is applied and the joint is completed (as is sometimes done with glued cartons before the glue has finally set), for to do so would wrinkle the tape and make the tube unacceptable. Of course, if the folded panels of the blank are properly aligned as it is taped, the tape will be coincident with and will completely cover a predetermined length of the gap, forming a squared and acceptable joint. In connection with a blank `having an elongated seam to be taped, even a few degrees of misalignment will be serious, because the relatively narrow tape will not be able to bridge the seam over its entire length.

The problem of alignment and gap control for a glued (rather than taped) carton, while less critical than for taped cartons, is still serious. A misaligned carton tube of glued construction will have a complete joint, as should be understood, but such a tube will be difficult to square up, and the lack of proper `gap dimensions may give rise to difficulties in closing.

The apparatus of the present invention is particularly characterized by the provision of means to correct any misalignment from initial folding stages and to control and to maintain the proper alignment of overfolded carton blank panels during final stages of the tube making sequence, to ensure the production of carton tubes having complete and accurately established joints, whether taped or glued.

The present invention represents a significant improvement in high speed folding machines of the type described and is specifically directed to apparatus for establishing accurate alignment of the folded-over panels of the carton blanks, especially larger sized asymmetrical and elongated blanks, preparatory to -or during the taping or gluing operations required to convert a flat-folded carton blank into a collapsed carton tube. A more specific aspect of the present invention is the provision of a new sword mechanism for improving the efficacy of a folding machine during the final stages of folding of the outer blank panels. A further aspect of the invention is the provision of new and improved guide belt apparatus for establishing and maintaining a predetermined gap and. a predetermined alignment between the opposed edges of flat-folded panels in the completion of the manufacturers joint, typically by the subsequent application of a tape over the gap. In accordance with the invention, the guide belt apparatus also contributes to the forward propulsion of a flat-folded blank through a folding machine as it passes from beneath the folding swords through a so-called transistion zone before passing beneath a series of press rolls.

For a more complete understanding of the invention and other of its attendant advantages, reference should be made to the following detailed description taken in conjunction with the accompanying drawings, in which:

FIGS. 1a, 2b, and 1c, taken together comprise a side elevational view of a folding machine embodying the inventive principles;

FIG. 2 is an enlarged plan view of anew folding sword means incorporated in the apparatus of the invention;

FIG. 3 is an enlarged, side elevational view of the sword shown in FIG. 2;

FIGS. 4, 5, and 6 are fragmentary, cross-sectional views taken generally along lines 4 4, 5 5, and 6 6, respectively, of FIG. 3;

FIG. Sais a supplementary, fragmentary, cross-sectional view of the sword;

FIG. 7 is an enlarged, fragmentary, side elevational view of the discharge end of the machine of FIG. l, including new guide belt means according to the invention;

FIGS. 8 and 9 are cross-sectional views taken generally along lines 8 8 and 9 9, respectively, of FIG. 7; and

FIG. 10 is a partial plan view of the new edge control apparatus for fiat-folded blanks.

Referring to FIGS. la, lb, and lc, the new and improved folding machine 10 is arranged in a straight line from a feed table, a printer-slotter, or a like feed stage 11 to the exit end 12 and generally includes lower transport frames 13 supported from three pairs of

stanchions

14, 15, 16, through transverse supporting bars. The lower transport frames 13, as shown in FIGS. la, lb, and lc, extend substantially for the ful length of the machine and may be adjustably, mutually spaced along the transverse bars to accommodate corrugated box blanks of all widths. Lower transport belts 17 are supported on rollers 18 provided along the upper edges of the frames 13. The lower belts 17, which are suitably driven, are adapted to engage central portions of a prescored carton blank as it is fed from the feed stage and to transport the blank through the machine in a straight path.

As is conventional in folding machines of this general type, a flat, unfolded, blank is fed into the machine from the feed stage 11 and is transported along a straight path, during which transport the blank is progressively folded along certain of its score lines. In the machine of the present invention, the blank may initially be transported through a prefold or pretreatment stage of the machine, in which the blank may be subjected to prewetting, prebreaking, glue coating or like treatments preparatory to folding the blank into a collapsed tube. Or, the blank may be delivered from a feed stage means, such as a printer-slotter, in which case the pretreatment operations, excepting perhaps gluing, might be omitted. The specific details of the apparatus for effecting the desired or necessary pretreatment do not represent part of the present invention and need not be further discussed in this application.

During transport of the blank through the prefold stage of the machine, it is engaged by soft rubber rollers 19 which are supported in upper frames Ztl, suspended from the stanchion pairs 14, along support bars and are vertically adjustable with respect to the lower frames to accommodate blanks of varying thicknesses.

After the at blank has traversed the pretreatment stage and while engaged by the opposed upper rollers 19 and lower transport belts 17, it passes through a vertical fold stage during which the outermost panels are engaged and progressively folded through 90 into a substantially upright position by folding belts 22 or equivalent folding means extending along the machine and in the path of the blank in a cooperative relation therewith. The folding belts 22 are supported in an adjustable and predetermined arrangement by folding belt frames 24 carrying folding belt pulleys 23.

Through the stages of feeding pretreatment, and vertical folding, the operation of the folding machine and the folding apparatus, itself, may be generally similar to that set forth in greater detail in the above-identified application. Likewise, the arrangement and operation of the lower transport belts and folding belts during a final at folding in which the outer panels are folded over through the final 90 of their 180 fold, and a pressing" stage, in which rolling pressure is applied to the blanks adjacent the fold line to sharpen the creases of the folded carton panels, are in general respects similar to that sct out in greater detail in the copending application. However, in accordance with the present invention, certain specific improvements in the controlled transport of the blank during the latter stages of tube formation, i.e., fiat folding and pressing have been incorporated into the machine of the present invention to ensure the formation of complete, square joints with precise gap control and alignment.

In accordance with one aspect of the invention, a blank B is controlled and guided during the initial portions of the fiat folding stage (the stage in which the outer panels are folded from a vertical or folded position to a horizontal fiat or folded position) by new and improved sword members 30 which are cantilever mounted, through appropriately bolted adapter members 29, from the ends of the upper transport frames 20, in superimposition with the lower transport belts 17. The swords 30 are multi-functional. That is to say, they provide straight edges about which the outboard carton panels are continuously and progressively folded through a substantial part of the fiat folding sequence by the folding belts 22; and they provide for controlled advancement of the blank in cooperation with the underlying lower transport belts 17. To those ends and in accordance with the invention, the swords 3() each include a horizontal blade 31 disposed in a plane generally parallel with that of the lower transport belts 17, and a tapered vertical blade 32 integrally connected to the horizontal blade, although terminating short of the end of the horizontal blade.

In accordance with the inventive principles, only the outer or creasing edges 33 of the horizontal blade 31 are actually in the plane of the advancing blank, as shown clearly in FIGS. 4-6. Thus, to minimize friction and resistance to the proper and smooth advance of the blanks, the creasing edge 33 projects downwardly from the major portion of the horizontal blade 31. However, to maintain control of the blanks, a series of

rollers

34a, 34h, 35 is supported in each of the swords to engage the upper surfaces of a blank and hold it against the lower transport belts 17. It should be clear, that this novel arrangement provides effective control over the blanks without introducing substantial drag on the advancing blanks as would otherwise be the case if the fiat underside 25 of the horizontal blade engaged, pressed against, or rested on the advancing blank. Moreover, the rollers prevent scoring of the blank by the swords in the event of a slight misalignment of the upper transport frames 20 with respect to the lower transport frames 13.

As a more specific aspect of the invention and to mini mize production costs, uniformly sized rollers 34a, 34h, can be used over large extents of the sword by periodically (in terms of blank advance) and progressively loeating the rollers further away from the outer creasing edges 33, in order to prevent the peripheral portions of the rollers from interfering with the progressively descending outer panels. This relationship is shown best in FIGS. 2, 4, and 5. More specifically, the initial rollers 34a are supported on rods 26a which are in turn appropriately supported from longitudinally extending adjustable rails 37. The rails 37 are adjustably bolted to the vertical blades 32 through spacers 38, as shown in FIGS. 2 and 4. The intermediate rollers 3411, which are identical in diameter to the rollers 34a are supported from rods 2Gb threaded to a longitudinal rail 39 bolted to the inside of the vertical blade 32. The rods 26h project through openings 28 in the vertical sword blade. As shown, in the final v reaches of the sword, where the vertical blade 32 is sharply tapered, rollers 35 of reduced diameter in comparison to that of rollers 34a, 34h are employed to accommodate flat folding of the outer panel portions of the advancing blank B. These innermost rollers 35 are supported from the tapered rails 39 on rods 35 in openings 27 formed at the intersection of the vertical and horizontal blades. As shown in FIG. 2, at the endmost portions of the horizontal blade 3l and beyond the termination of the vertical blade 32 there is absence of rollers to accommodate the complete and final flattening of the outer blank panels as they are advanced in the folding machine.

As a further aspect of blank control, the vertical sword blade 32 is progressively tapered along its length to accommodate the progressive infolding of the outer carton panels while preventing them from contacting or otherwise interfering with the upper portions of the

rollers

34a, 34h, 35. As shown in FIGS. 4-6, this is effected, in accordance with the invention, by maintaining the

rollers

34a, 3417, 35 within the right triangle defined by the cross section of the horizontal and

vertical blades

31, 32. To this end, the outer edges of the endmost ones of the intermediate rollers 3411 are beveled as shown in FIG. a, to be non-interfering with the descending blank.

Thus, it will be understood that at the flat folding stages of the machine, the central panel portions of the blank are advanced while sandwiched adjacent their edges between the lower transport belts 17 and the

rollers

34a, 34h, 35 as well as the creasing edges 33 of the horizontal sword blades 31. During this advance, the folding belts 22 engage the outer panels of the blank and cause them to be progressively and continuously folded about the creasing edge of the horizontal blade, as shown in FIGS. 4-6, into a completely flat-folded condition such as shown in FIG. 9.

In accordance with the invention, upon reaching a substantially flat-folded condition, but before leaving the controlled support of the swords, the edges of the blank are engaged by endless guide belts 40 (FIG. 10). The guide belts 40 are provided to maintain precise and accurate control of the blank during the last stages of the flat folding sequence and during its passage through the pressing and discharge stages of the machine. The guide belts also assist in the propulsion of the blanks through a transitory zone which extends from the ends of the swords to press rolls 50. Thus, while the folded blank is still under the control of the -swords 30 and lower transport belts 17, the outer creased edges E of the substantially flat-folded blank are engaged by vertically disposed (i.e., the plane of the belts is perpendicular to the plane of the horizontally disposed flat folded blanks) runs of the guide belts which are substantially parallel to the vertical sword blades 32. Also, in accordance with the invention, guide belts 40 are driven in predetermined relation to (usually in synchronism with) the blank advance as determined by the -speed of the transport belts 17. As shown in FIGS. 7 and 10, the guide belts 40 travel in endless loops about return sheaves 42, while receiving motive power from a drive sheave 52 driven in common with the drive sheave 17 for the lower transport belts 17.

In order to produce properly secured tubes and as explained hereinabove, it is imperative to adjust and to maintain the alignment and the spacing of the gap G of the opposed edges of the flat-folded blank, particularly where the panels are to be connected by a strip of tape. Accordingly, as an important aspect of the invention, the driven guide belts 40 are supported from the lower transport frames 13 in a frame 41 having sufficient flexibility to accommodate the requisite, precise belt adjustment. Thus, the guide belts 40 may be selectively adjusted to engage the tube edges and to urge the outer folded panels into said predetermined, uniformly gapped, properly aligned relationship and to maintain the relationship for the proper completion of the joint of the carton. As will be understood, the guide belts provide both traction (for advance of the blank) and a squeeze (for gap sizing), and the amounts of traction and squeeze7 may be precisely adjusted through the flexibility of the frame 41.

As 'shown in FIG. l0, the guide 4belt-s 4t) initially engage the flat-folded edges of the blank at points -adjacent and somewhat in advance of the ter-mini of the sword blades 31 (the beginning of the transition zone). In accordance with the inventive principles, the engage-ment of the guide belts 40 `with the blank continues uninterruptedly beyond the press rolls (the termination of the transition zone) and throughout the final transport of the blank through the folding machine. lD-uring this final transport, the flat-folded blanks yare pressingly engaged, adjacent the creases, by the press roll-s Si) Which are spring biased (FIG. 8) and supported from lpivot arms 53. The :press rolls are driven by the folding `belts 22 in a manner similar to that described `in more detail in the above-identified application. Specifically yand in .accordance with the present invention, the peripheral surfaces 51 of the press rolls 50 are annular and relatively wide in comparison with the diameter of the folding belts 22. Thus, the blanks will be engaged by bnoad surfaces including the roller peri-pheries and the folding elts. This effectively minimizes the possibility of scoring or otherwise marking the blanks by the rope-like folding belts 22 during the pressing stage, an important advantage when printed or specially fini-shed blanks are run through the machine.

In accordance with the invention, adjustment of the guide belts 4I) in Irelation to the path of the blank to icontnol dimensions and alignment :of the gap G of the completely folded blank is achieved :by supporting the guide belts within longitudinal guide belt frames 41, which frame-s themselves may be adjusted throughout their length. Typically, the gap adjustment required is such as to provide rfor gap widths on the order of one-eighth to one-quarter lof an inch. Thus, the frames are provided with sufficient fiexibility to be precisely adjusted along their length within that range, with additional adjustment range being afforded to enable an initially `wide gap to be narrowed down to the desired final dimension.

As shown in FIGS. 8-10, each guide belt frame 41 is substantially S-shaped in cross section, having upper and lower

horizontal flan ges

43, 44 connected by a vertical web 45. Appropriate openings 54 are formed in the upper flanges 43 of the guide belt frames 41 to allow the pivot arms 53 for the press roll-s 50 to `project therethrough. At predetermined, spaced clamping points along lits length (c g., 'four in a machine of typical size having guide belt frames of about 8 feet), the lower flange 44 is clampingly connected to a support arm 46 extending from the lower transport belt frames i3. At predetermined points (c g., three in the typical machine mentioned above) along its length and intermediate the clam-ping points, the lower flange 44 is connected to an adjusting screw 55 extending outwardly frorn the lower transport belt lframes 13. Thus, in accordance with the invention, the relationship of the guide belts 40 to the :carton tube edges E may be precisely adjusted at several points on each side of the folding machine. More speciically, the guide belt frames 41 may be adjusted by releasing clamp-ing bolts 56, received within openings 57 formed in the support arms 46, by means of pivotally connected eccentric clamps 58. The frame-s 41 are `moved to desired positions by the adjusting screws 55, and then the ercentric clamps 58 are pivoted downwardly to 'force clamping disks 59 upwardly against locking plates :or washers 60, thereby clamping the lower flanges 44 of the guide belt frames between the locking

plates

60 and 61 threaded on the end `of the bolts 56. As will be understood, the described clamping arrangement enables the guide belt frames to be locked in their precisely adjusted positions, after adjustment of the `widthwise spacing of the lower transport belt frames, enabling the gap G between the 'folded over panel edges to 'be carefully and precisely established and controlled by the belts 40 along the entire length of the carton tube. Most advantageously, the initial portions of the guide belt frames are so adjusted as to narrow the gap down from .an overly wide dimension to a desired dimension, usually in the one-quarter to one-eighth inch range, and the final portions of the guide belt frames are adjusted to maintain the desired final gap dimension and to accurately align the blank and gap. As an important aspect of the invention, once adjusted for a blank of specific fixed caliper, the guide belt frames need no further adjustment when the transport frame spacing is altered to accept wider or narrower blanks. However, if the caliper of the blanks is changed, then further adjustment of the guide belts is usually necessary.

As shown `in FIGS. 9 and l0, the upper flange 43 of the guide belt frame 41 supports a plurality of guide belt rollers 47 at regular and close intervals along its length. The rollers 47, along with the free edge 63 of the upper ange, are adapted to provide effectively continuous horizontal and vertical support for the guide belt 4f) and to maintain it in a vertical relation and in a substantially straight path parallel with that of the advancing carton blanks. in accordance with the invention, spaced, relatively rigid, non-deflectable guide plates 48 and 49 are also supported by the upper flange 43 to prevent the belts 40 from riding up or down along the rollers 47.

Further and more complete `details of the apparatus -illustrated in FIGS. la, 1b, 1c, and 7 and 8 not otherwise specifically identified and described hereinabove and not, by itself, representing a part `of the present invention may be had by reference to my U.S. Patent No. 3,270,628, in which a Universal Box Folding Machine of similar overall function and appearance is completely described and claimed` In accordance with one aspect of the invention, an associated taping machine 70 is located immediately adjacent `the discharge end 12 of the folding machine 10, The taping machine 70 generally includes a supply of gummed tape 71, which is mois-tened by an applicator 72 and dispensed and applied over the gap in a straight line parallel with the path of the blank. As shown, the taping machine 70 includes a plurality of opposed driving rolls 73 which are driven in synchronism from the main drive of the folding machine. The rolls 73 are adapted to engage and transport a flat-folded blank through the taping machine in the form it yhad upon leaving the folding machine it).

As explained hereinabove, if a blank is improperly aligned as it is fed through the taping equipment, the gap will be improperly taped and the resulting tube will be improperly formed. However, in accordance with the principles of the invention, the possibility of misalign ment is substantially precluded by engaging, guiding and aligning the creased edges of the flat-folded blank in the final stages of the folding machine until control thereof is assumed by the drive rolls 73 of the taping machine. That is to say, as a flat-folded blank is discharged from the folding machine in alignment and under the control of the precisely adjusted, driven guide belts 4t) and the press rolls 50, it is re-engaged by the driving rolls 73 while being maintained in the properly aligned relation with the taping machine.

Thus, in accordance with the invention, positive and accurate control of the blank is maintained at all times along its path through the folding and taping machines, first by the opposed upper rolls and lower transport belts; then by the folding belts, the swords and the lower transport belts; then by the folding belts, the ends of the swords, the driven side guide belts, and lower transport belts; then by the folding belts, the driven side guide betls, and the lower transport belts; and then by the guide belts, the pressing rolls, and lower transport belts; and finally by the opposed rollers of the taping machine. With this extensive and carefully adjusted control, the folded carton blanks may be taped or otherwise completed to form acceptable and readily squarable cartons, as should be appreciated.

The advantages of the precise control of the folded, corrugated blanks afforded by the apparatus of the invention may be especially appreciated in the processing of irregularly shaped, die cut blanks. Absent the new control apparatus, which provides continuous and uninterrupted control during the final folding stages (especially the transition zone thereof) such odd-shaped blanks having edges of unequal lengths or small blanks might easily become skewed or otherwise misaligned as they are sequentially folded and transported through the folding machine. However, in accordance with the inventive principles, proper alignment and advance of the carton blank is securely maintained throughout the final stages of the flat folding sequence, regardless of the shape or size of the blank, by the new and improved folding sword and guide belt arrangements.

lt should be understood that the specific apparatus herein illustrated and described is intended to be representative only, as certain changes may be made therein without departing from the clear teachings of the disclosure. Accordingly, reference should be made to the following appended claims in determining the full scope of the invention.

I claim:

l. Folding apparatus for paperboard blanks comprising (a) lower transport belt means for engaging the underside of a paperboard blank and conveying it along a predetermined straight path through vertical fold, fiat-fold and pressing stages;

(b) folding means arrayed adjacent said lower transport belt means and adapted to engage outer portions of said blank in said vertical fold and fiatfold stages to progressively and continuously fold said outer portions through and thereafter to press down upon said fiat-folded panels during said pressing stage;

(c) upper roller means adapted to engage the upper surface of said blank as it passes through said vertical fold stages;

(d) folding sword means arrayed above said lower transport belt means and adapted to provide straight edges about which said outer panel portions may be infolded during said fiat fold stage;

(e) vertically disposed guide belt means extending adjacent said predetermined path along at least a portion of said fiat fold stage and said pressing stage;

(f) means to drive said guide belt means in substantial synehronism with said transport belts and said folding means;

(g) said guide belt means being adapted to control and maintain a predetermined separation between the edges of the infolded outer blank portions;

(h) whereby said blank may be controllably supported in said fiat fold and `discharge stages by the cooperation of said lower transport belts, said folding means, said sword means and said guide belt means.

2. Folding apparatus in accordance with claim 1, in

which (a) flexible guide belt frames are provided for guiding and supporting said guide belt means; and

(b) means are provided for adjusting said fiexible guide belt frames.

3. Folding apparatus in accordance with claim 1, in

which said folding sword means includes (a) a first horizontally disposed folding blade portion including an outer folding edge;

(b) said horizontal portion defining a plurality of openings inwardly of said edge;

(c) a second vertically disposed blade portion joined to said first blade inwardly from the free edge of said first blade;

(d) means supporting said folding sword `from said folding apparatus with said horizontal blade portions parallel with said predetermined path and immediately above said transport belt means;

(e) said second blade portion being gradually convergently tapered and terminative short of the terminus of said first blade portion;

(f) a plurality of shafts having axes parallel to thc plane of said first blade portion;

(g) means supporting said shafts from said second blade portion;

(h) roller means mounted for rotation on said shafts;

(i) said roller means being disposed in said openings and having peripheral portions disposed in a horizontal plane which includes said folding edge;

(j) said roller means being confined within a right triangular cross-sectional area defined by the first and second folding blade portions.

4. Folding apparatus in accordance with claim 1, in

which said guide belt means includes (a) a pair of longitudinally extending guide belt frames;

(b) means supporting said frames from said folding apparatus adjacent and generally parallel with said transport belt means;

(e) a plurality of guide belt rollers rotatably supported in said guide belt frame along a predetermined path;

(d) a guide belt means supported in said guide belt frame by said guide belt rollers in a vertical relation adjacent said conveyor belt means and at generally right angles thereto;

(e) frame adjustment means operatively associated between said guide belt frame and said folding apparatus to selectively adjust the relationship of said frame to said apparatus along the length thereof in a manner whereby the alignment of said guide belt with said transport bolt may be precisely adjusted.

5. Folding apparatus in accordance with claim 1, which includes (a) means for applying a tape to the opposed, separated edges of said overfolded blank portions while said blank is maintained under positive control.

6. Folding apparatus in accordance with claim 1, in

which (a) said folding belt means is adapted to drive pressing rolls arrayed in said pressing stage;

(b) said pressing rolls have annular pressing surfaces which are comparatively wide in relation to the dimensions of said folding belt means.

7. Apparatus for for-ming a carton tube from a corrugated blank, including (a) means for conveying a blank along a predetermined path;

(b) means for overfolding outer panel portions of said blank into a superimposed relation with central portions of said blank with a gap between the opposed edges of said overfolded panel portions;

(c) driven guide belt means for engaging the lateral edges of said fiat-folded blank in a manner determinitive of the width of said gap;

(d) means for adjusting the relationship of said guide belts to said blanks for selectively varying the width of said gap and for establishing parallel alignment of said gap and said flat-folded carton blank with said predetermined path;

(e) means for .maintaining said blank and said gap in said predetermined alignment and fOr connecting said opposed edges.

8. Apparatus in accordance with claim 7, in which (a) said means for maintaining said blank and said gap in said predetermined Valignment and for connecting said opposed edges comprises a taping apparatus.

9. Apparatus for forming a carton tube from a corrugated blank, comprising (a) means in said apparatus forming verticalfold,

flat-fold and securing stages;

(b) a pair of driven lower transport belts extending throughout at least said vertical-fold and fiat-fold stages;

(c) upper roller means opposed to said lower transport belts and extending generally throughout and not substantially beyond said vertical-fold stage;

(d) a pair of folding means extending generally throughout said vertical-fold and said fiat-fold stages and arranged to engage and manipulate outer panel 10 portions of said blank through substantially of fold;

(e) a pair of folding swords mounted in opposed relation to said lower transport belts and extending beyond said upper transport belts throughout a portion of said flat-fold stage;

(f) a pair of driven side guide belts disposed along said lower transport belts and extending at least from points adjacent the terminal ends of said swords throughout the final portions of the flat-folding stage;

(g) means to effect lateral adjustment of said transport belts and swords;

(h) means to effect lateral adjustment of said side guide belts relative to said transport belts;

(i) a folded blank being engaged during terminal portions of said fiat-folding stage simultaneously by said lower transport belts on the bottom, said folding means on the top, and said side guide ybelts along the side edges, whereby to precisely align said blank and to predetermine the gap width along the adjacent edges of its overfolded panels;

(j) said securing stage including means to receive a thus precisely aligned blank and to secure said overfolded panels to each other.

10. Apparatus according to claim 9, `further characterized by (a) said securing stage comprising means for applying a narrow, elongated tape along the adjacent edges of the overfolded panels.

11. In a folding machine for corrugated container blanks or the like, including transport belt means adapted to engage the underside of a carton blank for transport in a predetermined straight path, an improved folding sword comprising (a) a first, horizontally disposed folding blade portion including an outer folding edge;

(b) said horizontally disposed portion defining a plurality of openings inwardly of said edge;

(c) a second, vertically disposed blade portion joined to said first blade portion and poistioned inwardly of said first blade portion;

(d) means supporting said folding sword from said blank folding machine with said horizontal blade portion parallel with said predetermined path and immediately above said transport belt means;

(e) said second blade portion being gradually convergently tapered and terminating adjacent the end of said first blade portion;

(f) a plurality of rods having axes parallel to the plane of said first blade portion;

(g) means supporting said rods from said second blade portion; and

(h) roller means monted for rotation on said rods;

(j) said roller means being generally confined within a right triangular cross-sectional area defined by the first and second folding blade portions.

12. A folding sword in accordance with claim 11, in

which (a) said rollers are disposed along the length of said sword progressively closer to said vertical blade portion and progressively further from said folding edge.

13. A folding sword in accordance with claim 12, in which (a) at least the endmost ones of said openings extend into said vertical blade portions;

(b) the endmost rollers are supported in said endmost openings in regions of intersection of said vertical and horizontal blade portions.

14. A folding sword in accordance with claim 11, in

which (a) said means suporting said rods include rails adjustably disposed in a substantially parallel relation with said vertical blade portions;

(b) at least one of said rails being spaced outwardly from said vertical blade portion and being disposed over said horizontal blade portion to support the most outwardly disposed ones of said rollers;

(c) at least another one of said rails being disposed immediately adjacent the inner side of said vertical blade portion and supporting the most inwardly disposed ones of said rollers.

15. A folding sword in accordance with claim 11, in

which (a) said folding edge projects downwardly from said horizontally disposed blade portion substantially into but not substantially beyond the plane of the peripheries of said rollers.

16. In a blank folding machine including transport belt means adapted to engage the underside of a carton blank for transport in a predetermined straight path through a folding means and means for completing a manufacturers joint, edge control means for regulating the relationship of edges of a transported blank during the folding thereof by said folding means comprising (a) a pair of longitudinal guide belt frames generally extending from said folding means to said means for completing a manufacturers joint;

(b) means supporting said frames from said folding machine adjacent and generally parallel with said transport belt means;

(c) a plurality of guide belt rollers rotatably supported in said guide belt frame along a predetermined path;

(d) guide belt means supported in said guide belt frames by said guide belt rollers in a substantially vertical relation adjacent said transport belt means;

(e) frame adjustment means operatively associated between said guide belt frames and said folding machine to selectively transversely adjust the relationship of said frames to said machine along the length thereof in a manner whereby the alignment of said guide belts with said transport belts may be precisely adjusted; and (f) means to drive said guide belts in substantial synchronism with said transport belts. 17. Edge control means in accordance with claim 16, in which (a) said adjustment means include a plurality of spaced clamping means and a plurality of adjusting screws disposed perpendicularly to said predetermined straight path. 18. Edge control means in accordance with claim 16, in which (a) said guide belt frames are of substantial S-shaped cross section and include horizontally disposed upper and lower anges interconnected by vertically disposed webs; (b) said guide belt rollers are supported on shafts projecting downwardly from said upper tlange; and (c) said guide belt frames are constructed and proportioned to have exibility in a horizontal direction to accommodate adjustment of a guide belt by deflection of one portion of a guide belt frame relative to `another portion. 19. Edge control means in accordance with claim 18, in which (a) auxiliary guide plates are supprted parallel with said upper flange; and (b) said auxiliary guide plates engage the top and bottom edges of said guide belts and maintain them in a predetermined relationship with said guide belt frame.

References Cited UNITED STATES PATENTS 2,701,990 2/1955 Fergnani 93-52 2,976,780 3/1961 Lopez et al 93-36 3,122,069 2/1964 Lopez 93-52 BERNARD STICKNEY, Primary Examiner.