US2851934A - Manufacture of envelopes - Google Patents

Description

p 1958 v. E. HEYWOOD MANUFACTURE OF ENVELOPES 2 Sheets-Sheet 1 Filed July 10, 1957 INVENTOR Win21? EMEYWOO D ATTORNEY v. E. HEYWOOD 2,851,934 MANUFACTURE OF ENVELOPES 2 Sheets-Sheet 2 :Ywo'oo ATTORNEY m mm Sept. 16, 1958 Filed July 10, 1957 mm kmm fmw .VN

United States Patent Office Patented Sept. 16, 1958 MANUFACTURE OF ENVELOPES Vincent E. Heywood, Worcester, Mass., assignor to United States Envelope Company, Springfield, Mass, a corporation of Maine Application July 10, 1957, Serial No. 670,981

8 Claims. (CI. 93-62) This application is a continuation-in-part of my copending application Serial No. 375,091 for Manufacture of Envelopes, which was filed August 19, 1953, now abandoned.

The present invention, like that of my United States Patent No. 2,772,611, dated December 4, 1956, for Envelope Making Method and Mechanism, deals with methods and means by which to obtain very rapid production of envelopes, through the elimination, in their continuous or rotary machine manufacture, of a certain production bottleneck which has heretofore always operated against any appreciable stepping up of such a machines rate of envelope production.

This production bottleneck of all previous rotary envelope-making machines results, as described in my aforesaid patent, from a sequence of operations that requires the successive envelope blanks to receive their imprints of seam-sticking glue whilst advancing rapidly in individualized or spaced-apart relation at the maximum speed of blank travel attained in the machine. That is to say, in all previous rotary machines, a definite limit or ceiling on blank speed (and thus on the machines rate of envelope production) is imposed by the effect of centrifugal force on the rotating segments or dies that are conventionally employed to imprint the seam-sticking glue, since such segments or dies must operate at perpiheral speeds that keep pace with the maximum speed of blank travel through the machine. Thus it follows, with any appreciable stepping up of such a conventional rotary machines rate of envelope production, that minute glue'particles thrown off centrifugally from the speeded up rotary dies or segments, will invariably accumulate on blank-contacting machine surfaces exposed between the advancing spaced-apart blanks, to quickly foul up the machines operation, and necessitate its stoppage.

In the method and apparatus of my aforesaid patent, notwithstanding the leeway for much faster envelope production afforded by the relatively low peripheral speed of its rotary seam glue imprinting device, the latters tendency to throw off glue centrifugally is still a production limiting factor, especially when envelopes of large size or being made.

Moreover, the advantageous overgumming of seal flaps, by the two-purpose rotary glue imprinting device of said patent, can be achieved only when the blanks are of substantially rhombic or diamond shape, presenting seal flap edges of the same angularity as the seam forming edges of their side flaps.

On the other hand, in rotary machine envelope manufacture by the novel flap holding and blank gluing sequences and arrangements of the present invention, no corresponding limitations are imposed, either on the machines rate of envelope production, or on the size or shape of the blanks which are converted thereby into envelopes.

Other and further objects and advantages of the instant invention will be made apparent by the following detailed description thereof taken in connection with the accompanying drawings, in which:

Fig. 1 is a plan view illustrating one form of the envelope making method and apparatus of my invention, but omitting, for the sake of clearness, certain glue receptacles and glue transfer rolls.

Fig. 2 is a vertical sectional view on the line 22 of Fig. l and showing also the elements omitted from Fig. 1.

Fig. 3 is a larger scale view of one of the envelopes produced by my invention, from blanks such as shown at the right-hand end of Fig. 1. I

Figs. 4 and 5 are views, similar to Figs. 1 and 2 respectively, of another form of my invention, Fig. 5 being a section on the line 5-5 of Fig. 4.

Like reference characters refer to like parts in the different figures.

My invention achieves extremely high speed envelope manufacture from flat blanks of any conventional shape, such as shown in Figs. 1 and 4 by the blanks A, A, each providing beyond its usual rectangular body portion 1 the opposite triangular side flaps 2, 2, and the opposite dissimilar bottom and seal flaps 3 and 4 respectively. It is contemplated that a succession of these or other appropriate blanks will be rapidly fed one by one, either from a supply stack, or, in the case of substantially rhombic shapes, from suitable cut-ofi devices operable on a traveling paper web. In any case, the successive blanks, such as A, A, by the action of suitable feed rolls or the like (not shown except at 5, 5 Figs. 2 and 5) are advanced rapidly, in spaced relation, to the illustrated mechanism, each with its bottom or back flap 3 leading, and with its inside surface uppermost; preferably each blank A, during its said advance, receives lines of scoring 2a and 3a at the bases of its side and bottom flaps.

The initial operation here, the same as in my aforesaid patent, is to fold inwardly the side flaps 2, 2 of each of the advancing spaced blanks A. For this purpose the mechanism, in the path of the rapidly advancing spaced blanks, provides conventional plowshare folding devices 6, 6 (see Figs. 1 and 4) having suitably arranged lower and upper feed rolls 7, 7 which continue each blanks advance at the same high speed imparted by the rolls 5, 5. The plowshare folders 6, 6 operate in the usual and well known manner to obtain, by each blanks movement therethrough, the inward folding on score lines 2a, 2a of its side flaps 2, 2 against its body portion 1 to give it the parallel side edge folds 8, 8, as shown by the blanks B and B, Figs. 1 and 4. In this partly folded condition, the successive spaced blanks, moving parallel to their side edge folds 8, 8, have their advance in the same direction (arrow x) continued by suitable high speed forwarding rolls 9, 9, operating at substantially the same peripheral speed as the preceding rolls 5, 5 and 7, 7.

In the form of my invention shown by Figs. 1 and 2, the successive spaced partly-folded blanks next encounter cooperating spaced sets of high speed rolls and low speed rolls (here shown at 10, 19' and 12, 12 respectively) which function as hereinafter described to collect said blanks progressively, for seam glue applying purposes, in the keep shingled sloW speed blank assembly shown at Y in Fig. 1. Close or deep shingling of envelope blanks is not, per se, new-having long been used, both with unfolded and partly-folded blanks, in the well known coating or spreading process of seal flap gumming, as exemplified by the patents of Novick No. 1,121,125, Pflanze No. 1,385,468, Novick No. 1,943,985 and Winkler et al. No. 2,132,227

The purpose and effect of such prior art close shingling is to dispose in adjacent relation, for continuous en masse gumming, the inside marginal surfaces of the blanks trailing seal flaps. When this close shingled blank as- 3 semblyffor continuous seal flap gumming, is established, the margins of the respective blanks leading back flaps, on the opposite or under side of the assembly, will also be exposed in similar adjacent relation. But such adjacency of the back flap marginal areas 'is of no avail, for flapgurnming purposes, because it is of the outside surfa ces rather th an'of theinside surfaces,'of said back lilap margins. However, in the instant blank assembly Y, as hereinafter described, the adjacency is of the inside rnarginal surfacesof the respective blanksleading back or bottomfiaps 3, 3.

Forthe progressive" formation ofthe illustrated blank --assembly Y, each partly folded blank B emerging from high speedrolls 9, 9 has its'advancecontinued by an adjacent highspeed blankforwarding means, here shown as consistingofa lower roll'10, and a cooperating pair of upper narrow rolls or-discs 10', 10', the latter engaging with each'blank along its opposite side edge folds 8, 8. Said narrow rolls 10', 10' are appropriately relieved, asshownatll, Fig. 2, so as to release each blank and discontinue its high speed advance, at the instant that its leading bottom flap 3 encounters and is seized "in the bite of a pair of "slow speed blank forwarding rolls 12,-12. 'The latter,'as a unit, are made adjustable (seearrows Fig. 2) toward and away from rolls 10, 10', to accommodate 'the'spacing to blanks of longer or shorter dimension,"measuredin the direction of blank travel -through the mechanism.

Rolls 12, 12 have a peripheral speed which is only a very-small fraction of the peripheral speed of the preceding rolls5, 5, 7, 7, 9, 9 and 10, 10'. Thus each partly folded blank'B, as it encounters the rolls 12, 12, has its speed of advance so drastically reduced that it is almost'entirelyovertaken by the next following fast moving blank, before the 'latter, in turn, is slowed down by 'said'r'olls 12 12. In other words, while such a following fast-moving blank isbeing' advanced by rolls 9, 9 and 10, 10 from position B to position B (see Fig. 1) the preceding blank, under the influence of the slow rolls 12, 12,will have moved forward only the short distance represented on Fig. l by the shingle dimension S.

The latter is the width of the narrow marginal inside surface area of each blanks leading bottom flap 3 which 'not overtaken by the next following blank, in the above described successive overtaking operations. Each such overtaking occurs in the absence of edgewise collision' between the respective slow moving and fast moving blanks, and always with the latter projected for- "wa'rd'in overlying' or topside relation to the former, by reason of high' speed rolls 10, 10', being arranged to operate,jas'shown'in Fig. 2, at a slightly lower level than the preceding high speed rolls 9, 9.

-Thus by conjoint action'of rolls 9, 9, 10, 10' and 12, 12, the successive partly folded blanks B, B are progressively collected in a slow moving closely shingled or stepped assembly, as indicated at Y in Fig. l. Therein each blank, except for an exposed narrow area ofwidth S- along "the inside margin of its leading bottom flap 3, is overlain and covered by the next following blank.

Beyond the "range of forward adjustment of the shingling rolls -12, 12, are provided suitable roller elements which continue the slow speed advance of the -shingled=blank assembly Y, and which serve also to spread or roll seam sticking glue onto the exposed narrow bottom'fiap margins of its constituent partly folded blanks. These rollerelements comprise a lower roll 13 and a cooperating upper roll which, for seam gluing of blanks such 'as'A, A with non-meeting side flaps, is made in two spaced sections 14, 14, mounted on a common shaft 15. The roller elements 13, 14 have the same low peripheral spe'ed as the shingling rolls'12, 12, so as to 'continue the lattersslow speed advance of the closely shingled blank assembly Y.

' The peripheral surfaces of the 'two'upper roll sections speed-forwarding means forpreserving and maintaining marginally glued'bottom flap 3', on its score line 3a. folding operation, for whicheach blank is conditioned Q4 14, 14 are continuously supplied with seam sticking glue by a conventional glue transfer roll 16, associated with a glue supply tub 17, as'shown in Fig. 2. 'This glue, by the slow rotation of the spaced roll sections 14, 14, is continuously and progressively spread onto the adjacently exposed inner surfaces of leading bottom flap margins of slow moving blank-'= assembly Y in two parallel stripes,- as indicated by-the stipling 18, 18 in Fig. 1. Any tendency of said bottom flap margins to be deflected upwardly, asbyadhesion 'to the-glue spreading rolls able high speed blank de-shinglingmeans are shown at 22, 22', in spacedrelation to'the slow speed rolls 13, 14. In the intervening space I provide suitable slow the closely shingled blank assembly Y and for continuing I its-advance at the same -slow=speed imparted thereto by the rolls 12, 12 and 13, 14. This intermediate slow 'speed forwarding means consists, as here shown, of'a lower roll 21 and a pair of -aligned cooperating narrow rolls or discs '21', 21', "the latter'engaging the shingled blanks along their overlapped sideedge folds 8, 8, be-

yond the outeredges of the rolled on'seam gluing 18. Said slow speed rolls 21, 21 are arranged for adjustment as a unit (see-arrows; Fig-2),- toward or away from the high speed de-shingling elements 22, 22',in the'same manner and'for the same purpose asthe" corresponding adjustment above described of the shingling rolls 12, 12, toward or away :from the high speed blank forwarding rolls 10, 10'.

Theinitial elements of my' afOresaid hi'gh spe'ed deshingling means comprisefas'here shown,- a lower roll 22 and a cooperating pair of narrow upper rolls or discs 22', the latter enga'gihg each" arriving blank by-- its side edge folds 8, 8, beyond the'outer ends of its'r'narginal bottom flap gumming. 'Said' narrow' rolls22'- are appropriately relieved, as shown at 23, Fig." 2, to obtain intermittently the one' by one seizure andspeed up of successive front blanks of assembly Y,- as each, by said assemblys slow t'ravel, "is-moved' i'n'to' -seizu're position, in the interval during 'which 'the" reliefs 23- a're opposite the-roll 22. Each seized blanks speedup is-very drastic,

since rolls 22, 22, operate at-the same-high peripheral "speed'as the preceding"blank' forwarding rolls 5, 5,7, 7,

9, 9, and '10, "HQ-thereby in this progressive de-shingling of the blanks to 'reSto're to each in t'u'rnits original high speed of advance and its' s'p'ac'ed relation to the" blank next following.

This same high peripheral speed is also imparted to immediatelyadjacent' rollerelements, consisting as here shown of a lower drum or cylinder'24 and a'pairof cooperating-narrow rolls or 'discs 24' for seizing and forwarding each speeded upblank' by its side edge folds 3, 8, before the latter are released by'the'reliefs 23' of the preceding narrow high "s'p'e'ed"rolls 22. Said"elements 24, 24' besides"participating, as above/described,

in these successive high speed dc-shingling operations, at

the leading end of blank assembly Y, are also involved in the ensuing folding over of each de-shingled' blanks This by being individualized through its high speed pull out from the shingled asserhbly'Yfmay 'beper'formed, as here'shown, by an" arrangement "similar in" character to that disclosed for bottom flap folding in my aforesaid Patent No. 2,772,611.

That is to say, the drum cylinder 24 is shown in Fig. 2 as mounted, for its high speed rotation, on a stationary hollow shaft 25, whose interior is connected to any suitable source of suction, such as a vacuum pump, not shown. Stationary hollow shaft 25 has a longitudinal port 26, of substantially 90 circumferential extent, with which is adapted to register periodically the inner end of a passage 27 extending radially through the cylinder 24, and terminating on its periphery in an elongated slit or slits, for the suction seizure, on each revolution of said cylinder, of a so-individualized fast moving blank.

The high speed counterclockwise rotation of cylinder 24 is so timed to the high speed blank travel, that each blank is suction seized at or just behind its score line 3a, by the terminal slit or slits of passage 27, as the latter, substantially at the top of its travel, comes into communication with the port 26 of shaft 25. The blank 18 is shown in Figs. 1 and 2 as having been thus suctionally seized and drawn downwardly, by the cylinders rotation, toward the line of bite between said cylinder 24 and an adjacent pressing and forwarding cylinder 28, which rotates clockwise at the same high peripheral speed as that of cylinder 24.

Cylinder 28 is mounted, for its high speed rotation on a stationary hollow shaft 29, also connected to said source of suction, and providing a longitudinal port 30, of substantially 90 circumferential extent, with which is adapted to register the inner end of a radial passage 31 of cylinder 28. Said passage 31 terminates on said cylinders periphery in an elongated slit or slits for the suction seizure, on each revolution of said cylinder, of each individualized blank which, as above described, is drawn downwardly by the cylinder 24.

The respective ports 26 and 30 of hollow shafts 25 and 29 are so positioned, as shown in Fig. 2, that suction through passage 31 becomes available, for blank seizure by cylinder 23, substantially coincidental with the cut-off of suction through passage 27, to release such blank from the cylinder 24. The transfer of each blank, from cylinder 24 to cylinder 28 occurs as their respective suction passages 27 and 31 come into opposing substantial alignment, with the passage 31 seizing the blank in the same location as passage 27, viz. at or just behind its score line 311. As each blank moves downwardly (see B with cylinder 24, its forwardly projecting glued bottom flap 3, ahead of said score line, is deflected upwardly, away from, contact with the oppositely traveling surface of cylinder 28, by engagement with a suitable stationary guard plate 32 (see Fig. 2). I

Such deflection tends to bend upwardly each bottom flap 3 on its suctionally gripped score line 3a, said bending, in the case of blank B Fig. 1, being reflected by a foreshortening of its bottom flap 3. Said bending increases, and ultimately becomes a pronounced transverse fold (see 33, Figs. 1 and 3) as the downward high speed movement, first by cylinder 24 and then by cylinder 28, carries each blank, score line leading, between said two cylinders. The latters pressing action accentuates said fold, and then is exerted on each individualized blank, to obtain effective overlapped adhesive seam connection for pocket-forming purposes, between its bottom flaps marginal wet gluing 34 and the proximate edges of its previously infolded side flaps 2, 2.

With each individualized blank thus converted in sucsession by the folding in of its bottom flap 3, to a pocketed element, moving downwardly, fold 33 leading 'on cylinder 28, its release from said cylinders suction passage 31 takes place on latters at the bottom of its travel, beyond the port This transfers the advance of each pocketed element (a complete envelope except t'or seal flap gluing) to the bite between cylinder 28 and a cooperating lower roll which rotates counterclockwise at the same high peripheral speed as said cylinder. It will be understood that successive pocketed elements arriving one after another between cylinder 28 and roll 35 are projected forward in spaced relation at the same high speed of movement as the successive flat blanks A. A are fed to the mechanism by the rolls 5, 5, 7,7 and 9,9.

My invention contemplates applying of glue to the trailing seal flaps 4, 4 of these pocketed elements (complete envelopes with unglued seal flaps) by the prior art spreading or coating process, substantially in the manner disclosed in the aforesaid Novick Patent No, 1,121,125. For the required close shingling, to bring into adjacency the inside marginal areas of the respective trailing seal flaps 4, 4, each pocketed element emerging from rolls 2%, 35 has its advance continued by adjacent high speed forwarding means, here shown as consisting of a lower roll 36 and a cooperating pair of upper narrow rolls or discs 36, 36' for engaging each element along its opposite side edge folds 3, S. Said narrow rolls 36', 36 are appropriately relieved, as shown at 37, Fig. 2, so as to release each pocketed element, and discontinue it high speed advance, substantially at the instant that its side edge folds 8, 8 encounter and are seized by low speed shingling devices, here shown as consisting of a lower roll 4% and a cooperating pair of upper narrow rolls or discs 49', 49, for engaging the successive pocketed elements by their side edge folds 8, 8. Slow speed rolls 4%, 46' as a unit are made adjustable toward and away (see arrows, Fig. 2) from the high speed rolls 36, 36', to accommodate the spacing to pocketed elements of longer or shorter dimension, measured in the direction of their travel through the mechanism.

Rolls 40, 49' have a peripheral speed which is only a very small fraction of the peripheral speed of the preceding rolls 36, 36. Thus each pocketed element, as it encounters the rolls 4%, 40' has its speed of advance so drastically reduced that it is almost entirely overtaken by the next following fast moving pocketed element, before the latter in turn is slowed down by the rolls 40, 4%). in this overtaking or shingling action, provision is made for each fast moving pocketed element to be projected beneath the preceding slowed down pocketed element, by disposing the bight of slow rolls 40, 46 at a slightly higher level than the bight of fast rolls 35, 36' (see Fig. 2), and providing an upwardly sloping guide or skid 39 between said roll pairs to direct the bottom edge folds $3 of successive pocketed elements between the rolls 46, Additionally, for the same purpose, the lower high speed roll 35 is formed centrally with a raised projection 32 which, following release of each pocketed element by the reliefs 37, is adapted to elevate said elements trailing seal flap 4, so that the leading bottom edge fold 33 of the next following fast moving pocketed element will always be projected, by rolls 28, 3S, beneath said trailing seal flap.

Thus by conjoint action of rolls 28, 35, 35, 35' and 40, 44), the successive spaced apart pocketed elements are progressively collected in a slow moving closely shingled or stepped assembly, as indicated at Z in Fig. 1. Therein each pocketed element overlies and covers the next following pocketed element except for an exposed narrow area, of shingle dimension t, along the inside margin of the latters trailing seal flap 4, Beyond the range of forward adjustment of rolls 4%, 40' I provide suitable means for rolling or spreading glue, for envelope sealing purposes, upon the adjacent exposed trailing seal flap margins of the pocketed elements of the slow moving shingled assembly Z. Such means, as shown, consists of a lower roll 41 and an upper roll 42, both operating at the same low peripheral speed as the shingling rolls 40, 40' to continue the latters slow speed advance of the shingled assembly Z.

The periphery of upper roll 42 is continuously supplied with seal flap glue by a conventional glue transfer roll 43, associated with a glue supply tub 44, as shown in -Fige 2. This glue bythe slowirotationiofiroll 42 is continuously-sand progressively spread onto 1 the exposed trailing sealflap 'marg'insof the slowmoving assembly Z, in a wide band 'or stripe, as indicated by the' stippling 45 -in Fig.1. Thus eachpocketed element of said assembly 46 and-cooperating upper narrow rolls or discs 46,'46',

the latter contacting the:shingled assemblyZ beyond its gluing'45. Said rolls-"46, 46rhave the same low peripheral-speed astheshingling rolls 40,-, thereby to maintainintact the shingled assemblyZ and to deliver same progressively at. slow speed 'to' a suitably elongated drying conveyor. The latters-receiving' end is here indicate by conventional lowerrand-upper pairs of pulleys 47, 47, which, in conjunction .with other pulleys, not shown, carry the usual-narrow lower and upper pairs of elongated endless traveling belts-48, '48, adapted to contact opposite surfaces of the overlapped envelopes along their side edges, beyondwthe wet gluing on their seal flaps, to convey them, in shingled assembly, through a drying tunnel or the like, not shown.

In the form of my invention shown by Figs. 4 and 5,

the successive spacedapart partlysfoldedblanks B, B,

beyond the high speed forwarding rolls 9, 9, undergo as before a topside shingling operation in which each blank is partially overtaken and overlapped by the one next following. But this topside shingling is here used to collect the blanks for seam gumming, not in a close order assembly such as shown at Y in Fig. l, but rather in the shallowly shingled assembly shown in Fig. 4 at F, which assembly F,'except for its being produced 'by topside overtaking of each blank, is similar to the shallowly shingled blank assembly shown at .E in Fig, l .of my aforesiad Patent No. 2,772,611.

For the progressive formation of theillustrated blank assemblyF, eachpartly folded blank B emerging from high speed rolls 9,-'9 -has its advance continue d by adjacent high speed forwarding means, here shown as consisting of a lower roll and a cooperating pair of upper narrow'rolls or discs 50', 50', the latter engaging with each blank along its opposite side edge folds 8, 8. Said narrow rolls 50, 50' are appropriately relieved, as shown :at' 5-1,"Fig. 5, so as'to release each blank and discontinue its high speed a'dvance, at the instant that its leading back or bottom flap 3 encounters and'is seized in the bite of a pair ofslower speed-blank forwarding rolls 52, 52. The latter, as a unit, are made adjustable (see arrows Fig. 5) 'tow'ard' and away from the rolls 50, 50, to acc'ommodate the spacing to blanks of longer or shorter dimension, measured in the direction of blank travel.

each partly folded blank B, as it encounters the rolls '52, 52, has its speed of advance'so reduced that it is overtaken for about one-halfof its length by the next following fast moving blank B, before the latter, in turn, is slowed down by said rolls 52, 52. In other words,

while' 'such afollowing fast moving blank is being advanced by rolls 9, 9 and 50, 50' from position B to position B (see Fig. 4) the preceding blank, under the influence of the slower rolls 52, 52 will have moved forward slightly less than one-half as far, i. e., to a position B Fig.4, wherein its trailing'seal'flap 4 and parts of 1 its infolded side flaps 2, 2 are overlain by'the forward portion of the following blank B. V

' Thus it is "by"thesesuccessive overtakings that the partly folded blanksare collected progressively in the illu'strated shallowly shingled assembly P, which advances" To obtain. constant advance of blank assembly F, atlthe same reducedspeed imparted byxshingling rolls 52, 52, the-mechanism has three sets .of suitablyspaced lowspeed forwarding rolls, whichzhave. engagement. or. bite with the assemblys successive blanks alongtthe.lattersiside edge folds 8, 8. Eachrof these setsof lowspeed rolls consists of a lower roll53 and arpair ofalined' cooperating upper narrow rolls or discs 53', 53', all havingthe same low. peripheral speed as the shingling'rolls 52, 52, so as to keep the assembly F intact during the imprinting of seaming gluealong the successive blanks leading back flap margins, which .marginsin said assembly are spaced apartby the reducedrdistance d, Fig. 4.

The seam glue imprinting means is here shown as interposed between the first. and second sets of low speed forwarding rolls 53, 53. Saidimprinting means comprises a lower or. platen roll 54, and an upper shaft 55 of smaller .diameter than said platen roll 54. Said shaft 55 is formed with a pair ofspaced narrow raised helical ribs 56,. 56 of opposite inclination, such that eachribs'outer surface, by the rotation of shaft 55, moves in a circumferential path whoselength is .the reduced distance d (Fig.4) that separates the successive. leading back flap margins of the overlapped blanks of assembly F. Outwardly of the helical ribs 56, 56, the shaft 55 is formed with narrow collars orflanges 57, 57. for cooperation with the platen roll 54, to maintain the slow speed advance of assembly F, by engagement with itsconstituent blanks along their side edge folds 8, 8.

At each rotation of shaft 55, the outer surfaces of its helical ribs 56, 56 receive wet glue from their contact with a rotating overhead glue roller 58 (Fig. 5) which is 'vergent seam glue imprints as shown at 60, 60, Fig. 4.

Beyond the final (left-hand) set of slow speed forwarding rolls 53, 53, each foremost blank; of assembly F, is, in its turn, seized, speeded up, and'pnlled away from said assembly by the same high speed de-shingling means 22, 22' as are employed in Figs. land 2 for. de-shingling the successive foremost blanks ofthe blank assembly Y in said first-described form of my invention. Beyond said high speed de-shingling means 22, 22' of Figs. 4 and 5, the successive blanks are handled and converted into envelopes in exactly the same fashion, and by exactly the same means, as described above for Figs. 1 and 2, Since said handling and converting means in Figs. 4 and 5 are designated by the same reference characters as are.v used in Figs. l and 2, it is not necessary here to describethe same in further detail.

Any suitable gearing, not here shown, may be employed to impart to the several rolls their respective high peripheral speeds, and low peripheral speeds, as herein specified. Also, the illustrated mechanism, in addition to its adjustments above described for various lengths of blanks, can readily be accommodated to the handling of different widths of blanks, merely 'by adjusting, toward or away from center line 22 of Fig. 1 (or center line 5--5 of Fig. 4), the positions of the several sets of narrow forwarding rolls 10, 21, 22, 24', 36', 40, 46, 50 and 53 on their respective shafts.

Under all conditions, and regardless of the shape or size of the blanks being handled, my invention makes possible the rotary machine mznufacture of envelopes at much higher rates of production than ever achieved heretofore. This results from my herein described sequence of envelope making operations which obtains all blank gluing, both for seal flap and seam sticking purposes, without any limiting effect whatsoever on the speed of blank movement to and through the machine.

Actually, the envelope production rate, in the preferred form of my invention shown in Figs. 1 and 2, is limited only by the speed at which it is practicable and feasible to perform on the blanks in process the two described flap folding operations, viz., for each blank, the initial infolding of its side flaps, and the subsequent folding over of its marginally glued back or bottom flap into adhesive seam connection with its side flaps. in other Words, the rate of envelope production suffers no limitation or curtailment whatsoever, from the operations of applying to successive blanks (l) the seam sticking glue and/ or (2) the seal flap glue. This is because of the fact that the gluing is applied, progressively and en masse, to inside seam flap margins as well as to inside seal flap margins of the successive blanks, with the latter collected, for each glue applying operation, in a slow speed closely shingled or stepped assembly that exposes only the desired glue-receiving inside flap margins to the action of the gluing roller or wiper.

I claim:

1. In the manufacture of envelopes from a succession of flat blanks advancing at high speed in spaced relation with their bottom flaps leading, the improvement which consists in folding inwardly the side flaps of the successive so-advancing spaced blanks, so progressively collecting the successive so-folded blanks in a low speed closely shingled assembly as to expose in adjacent relation, for continuous en masse gluing, the inside surfaces of the respective blanks leading bottom flap margins, progressively spreading glue, by the low speed advance of said assembly, upon the so-exposed adjacent inside marginal surfaces of said leading bottom flaps, speeding up in succession each soglued blank to restore its initial high speed of advance and its spaced relation to the blank next following, folding inwardly the bottom flaps of the successive speeded-up blanks, to produce, by adhesion of said bottom flaps to the previously infolded side flaps, a succession of pocketed elements, so progressively collecting the successive pocketed elements in a low speed closely shingled second assembly as to expose in adjacent relation, for continuous en masse gluing, the inside surfaces of the respective elements trailing seal flap margins, and progressively spreading adhesive by the slow speed advance of said second assembly, upon the adjacent so-exposed trailing seal flap margins of the so-shingled pocketed elements.

2. In the manufacture of envelopes from a succession of flat blanks advancing at high speed in spaced relation with their bottom flaps leading, the improvement which consists in folding inwardly the side flaps of the suc- .cessive so-advancing spaced blanks, so progressively collecting the successive so-folded blanks in a low speed closely shingled assembly as to expose in adjacent relation, for continuous en masse gluing, the inside surfaces of the respective blanks leading bottom flap margins, progressively spreading glue, by the low speed advance of said assembly, upon the so-exposed adjacent inside marginal surfaces of said leading bottom flaps, speeding up in succession each so-glued blank to restore its initial high speed of advance and its spaced relation to the blank next following, folding inwardly the bottom flaps of the successive speeded-up blanks, to produce, by adhesion of said bottom flaps to the previously infolded side flaps, a succession of pocketed elements, so progressively collecting the successive pocketed elements in a low speed closely shingled second assembly as to expose in adjacent relation, for continuous en masse gluing, the inside surfaces of the 10 respective elements trailing seal flap margins, progressively spreading adhesive by the slow speed advance of said second assembly, upon the adjacent so-exposed trailing seal flap margins of the so-shingled pocketed elements, and continuing the slow speed advance of said second assembly for the drying of the adhesive on said seal flaps.

3. In envelope making mechanism, means for advancing fiat blanks at high speed in spaced relation, with their bottom flaps leading, means operative on each so-advancing blank to fold inwardly its side flaps, means for so pr0 gressively coilecting the successive so-folded blanks in a low speed closely-shingled assembly as to expose in adjacent relation, for continuous en masse gluing, the inside surfaces of the respective blanks leading bottom flap margins, means for progressively spreading glue, by the slow speed advance of said assembly, upon the so-exposed adjacent inside bottom flap margins of the successive shingled blanks, means for restoring in succession to each so-glued blank its high speed advance and its spaced relation to the blank next following, means for folding inwardly in succession the bottom flaps of the speeded-up blanks to produce, by adhesion of said bottom flaps to the previously infolded side flaps, a succession of pocketed elements, means for so progressively collecting the successive pocketed elements in a low speed closely-shingled second assembly as to expose in adjacent relation, for continuous en masse gluing, the inside surfaces of the respective elements trailing seal flap margins, and means for progressively spreading glue, by the slow speed advance of said second assembly, upon the adjacent so-exposed trailing seal flap margins of the so-shingled pocketed elements.

4. In envelope making mechanism, means for advancing flat blanks at high speed in spaced relation, with their bottom flaps leading, means operative on each so-advancing blank to fold inwardly its side flaps, means for so progressively collecting the successive so-folded blanks in a low speed closely-shingled assembly that each blank, ex-

cept for the margin of its leading bottom flap is overlain by the next-following blank, means for progressively spreading glue, by the slow speed advance of said assernbly, upon the so-exposed adjacent bottom flap margins of the successive shingled blanks, means for restoring in succession to each so-glued blank its high speed advance and its spaced relation to the blank next following, means for folding inwardly in succession the bottom flaps of the speeded-up blanks to produce, by adhesion of said bottom flaps to the previously infolded side flaps, a succession of pocketed elements, means for so progressively collecting the successive pocketed elements in a low speed closelyshingled second assembly that each element, except for the margin of the trailing seal flap of its blank, underlies the preceding element, means for progressively spreading adhesive, by the slow speed advance of said second assembly, upon the adjacent so-exposed trailing seal flap margins of the so-shingled pocketed elements, and means for continuing the slow speed advance of said second assembly for the drying of the adhesive on said seal flaps.

5. In the method of making envelopes from a succession of flat blanks advancing in spaced relation with their bottom flaps leading, the improvement which comprises folding inwardly the side flaps of the successive so-advancing spaced blanks, successively retarding the advancing so-folded blanks such that each blank is superimposed upon the preceding blank to the extent that only the leading marginal edges of the bottom flaps are uncovered, spreading glue on the so-exposed leading marginal edges of said bottom flaps, successively accelerating the advancing so-folded and so-glued blanks so as to provide another spaced relationship between successive blanks, folding inwardly the bottom flap of each blank in succession so as to form a succession of pocketed elements, successively retarding the advancing pocketed elements such that each element, except for the exposed marginal edge of its trailing seal flap, underlies the preceding element,

,and, spreadi g ,gl.ue upon the so-exposed trailing seal flap :margins.

;6. lnlan-envelopemaking machine, means'for-iadvanc- .ing .flat envelope blanks in spaced relation with; their bottom, flaps leading, means forfolding inwardly the side flaps of each advancingblank, means for successively retarding 'theso-folded blanks such that each blank is superimposed upon the next preceding blank to the; extent that only the marginal edges of the leading bottom flaps vare exposed, means for wiping glue on the so-exposed ."marginal edges of said bottom flaps, means for succes- -sive1y accelerating the so-glued blanks, means for folding inwardly ingsuccession the bottom flaps of said blanks so -as:to; produce a succession of pocketed elements,--means for; retarding in succession the advancing pocketed elements-such-that:each-element,-except for the exposed .marginal-edgeof itsv trailing seal flap, underlies the prercedingielement, and means for wipingglue upon the exposed marginal; edges, of; said :trailing seal flaps.

7. In 'the'manufacture of envelopes from a succession oftflat blanks advancing athigh speed inspaced relation withtheir back or bottom flaps leading, the, improvement which consists of folding inwardly the, side flaps of the successive so-advancing spaced blanks, reducing at the same point in .each partly foldedblanks movement its speed of advance, .such that each blank is superimposed upon the preceding blank, in a progressivelyformed shingled blank assembly moving at said reduced speed, applying glue, during the slow speed advance of said blank assembly, to the respective inside leading marginal surfaces of the successive back or bottom flaps of said assemblys constituent blanks, speeding up in succession each so-glued blank to restore its initial high speed of advance and its spaced relation to the blank next follow- "ing,folding inwardly the bottom flaps of the successive speeded-up blanks, to produce, by adhesion of said bottom' flaps to the previously infolded side flaps, a succesing fiat blanks at high speed in spaced relation with their back or bottomfiaps leading, means operative on each so-advancing blank to fold inwardly its side flaps, means for reducing at the same point in each so-folded blanks movement its speed of advancement, such that each blank is superimposed upon the preceding blank in a p rogressively formed shingled blank assembly moving at said reduced speed, means for applying glue, during the slow speed advance of said blank assembly to the respective inside leading marginal surfaces of the successive back or bottom flaps of said assemblys constituent blanks, means for restoring in succession to each so-glued blank its high speed advance and its spaced relation to the blank next following, means for folding inwardly in succession the bottom flaps of the speeded-up blanks to produce, byadhesion of said bottom flaps to the previously infolded side flaps, a succession of pocketed elements, means for so progressively collecting the successive pocketed elements in a low speed closely-shingled second-assembly as to expose in adjacent relation, for continuous en masse gluing, the inside surfaces of the respective elementstrailing seal flap margins, and means for progressively spreading glue, by the slow speed advance of said second assembly, upon the adjacent so-exposed trailing; seal flap margins ofthe so-shingled pocketed elements.

No references cited.

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