US2673497A

US2673497A - Machine for the manufacture of envelopes and flat bags with inside arranged folding seams

Info

Publication number: US2673497A
Authority: US
Inventors: Heitmann Hans
Original assignee: Individual
Current assignee: Individual
Priority date: 1950-05-04
Filing date: 1950-05-04
Publication date: 1954-03-30
Anticipated expiration: 1971-03-30

Description

March 39, 1954 I H. HEITMANN 2,573,497 MACHINE FOR THE MANUFACTURE OF ENVELOPE-S AND FLAT BAGS WITH INSIDE ARRANGED FOLDING SEAMS 1950 4 Sheets-Sheet 1 Filed May 4 H. HEITMANN March 30, E 954 m MANUFACTURE OF ENVELOPES AND INSIDE ARRANGED FOLDING SEAR/ES 4 Sheets-Sheet 2 MACHINE FOR 'l'h' FLAT BAGS WITH 1950 Filed May 4 filiorree March 30, 1954 H HE|TMANN 2,673,497

MACHINE FOR THE MANUFACTURE OF ENVELOPES AND FLAT BAGS WITH INSIDE ARRANGED FOLDING SEAMS Flled May 4, 1950 4 Sheets-Sheet 3 Mal-ch30, 1954 H. HE MACHINE. FOR THE MANUP FLAT BAGS WITH INSIDE Filed May 4 1950 T ACTURE OF ENVELOPES AND D FOLDING SEAMS 4 Sheets-Sheet 4 Patented Mar. 30, 1954 2,673,497 MACHINE FOR THE MANUFACTURE OF EN- VELOPES AND FLAT BAGS WITH INSIDE ARRANGED FOLDING SEAMS Hans Heitmann, Berlin-Neukolln, Germany Application May 4, 1950, Serial No. 159,896

9 Claims. 1

The invention relates to a machine for the manufacture of envelopes and fiat paper bags with inside arranged folding seams in which a web of paper or another suitable material is continuously fed from a supply roller and the work pieces are severed after being printed and folded and the folded seams being glued together, said machine operating preferably by means of rollers. The object of the invention is to provide a machine of this type by which envelopes or folded bags with or without gummed flaps or with or without folded flaps may be produced. The machine is adjustable with the simplest means so that the manufacture of diiferent sizes of work pieces is possible. It is a further object of the invention to provide a machine which can be supervised from the floor on which it stands without using running boards or the like.

The object of the invention is the improvement of the conventional folding machine working with rollers by which fiat bags with inside arranged folding seams on both sides are manufactured, which improvement consists essentially in the provision of a switching device for conducting the work pieces, after the bottom and the closing flaps have been cut out simultaneously, either through a dryer, if the work pieces are provided with a gummed closing flap, or, without being gummed, directly to a pair of transporting ro1lers having a folding device for the closing flap which folding device may be disconnected, and finally to the storing device.

Therefore the same machine can be used for making envelopes and folded bags either with or without a gummed closing flap and either with or without folding the closing flap.

A further feature of the invention consists in the provision of a machine in which the working rollers for printing, gumming, cutting and folding of the work the main shaft of the machine, while the speed of the supply rollers of the original webof material can be adjusted by the use of a change speed wheel. Because of this adjustment, only one pair of gummers is required for gumming the bottom flaps of all work pieces to be worked by the machine and also only one cutting roller for cutting out the interior folding seams of all work pieces to be worked by the machine. For changing the machine to produce envelopes or bags of a diiferent size only one different change speed wheel is required and one different printing cylinder the diameter of which is adapted to the new feeding speed to avoid erasing of the printing on the work piece -web.- r

pieces rotate synchronously with iii Further according to the invention, only one form cutter or cut off knife is necessary for cutting the bottom flaps and a second one for cutting the closing flaps of all work pieces to be worked by the machine. For simultaneously cutting the closing flaps and cutting out the bottom flaps a spiral-shapedrotating knife is used which is relief-milled in such a way that the running cutting edges roll off point for point along the fixed fiat inclined lower knife like scissors so that also shapes having an acute angle may be cut. Preferably the form cutter is yieldingly pressed against the counter-cutter f. i. by inserting pressure springs between the cutter carrier and the form cutter, and the form cutter is accelerated in the cutting moment so much that the feeding speed of the web corresponds to the speed of rotation of the form cutter. The special construction of the form cutter cooperating with a stationary lower cutter makes it possible to cut shapes having an acute angle without the cutting edges becoming untimely blunt. The cutting angle of the form cutter is so chosen that the latter may be used for great and small work pieces, a fact of greatest importance for the manufacture of envelopes with pointed closing flap. The fact that the bottom flaps and the closing flaps of all work pieces having closing flaps pointed at the same angle overlap for the same amount is also advantageous for the manufacture of closing flap gummers as only one gummer may be employed for all sizes. The form cutter may be shaped for cutting rectilinear or curved lines. In consequence of the acceleration attainable f. i. by an adjustable cam, one sole form cutter can be used for dilferent feeding speeds of the web i; e. for different fed lengths, provided the section lines are similarly shaped.

A further feature of the invention is that the work pieces are received by the work piece holders of the drying conveyor chain so that their fully opened closing flaps are rearwardly directed relatively to the feeding direction, and that, while the work pieces run through the dryer, the whole surface of the gummed portions of the bottom flaps are pressed on. Each work piece holder consists of a solid and a yielding portion, two

neighbouring work piece holders acting together in sucha way that the desired surface of the bottom flap is pressed between the solid portion of one holder and the yielding portion of the second holder. The surface exposed to the pressure is so dimensioned that with every work piece size within the limits of adjustability of the machine,

the whole gummed portion of the bottomv flaps is pressed, in contradistinctlon to the usual linelike pressure. Adjustment of the work piece holders or of the conveying means carrying them with respect to each other or with respect to the remaining part of the machine in the transverse direction of the latter is not necessary.

The lower part of the work piece holders is so shaped, according to the invention, that the distance between the center lines of the swing axes of the holders is twice as great as the distance between the center lines of adjacent work piece holders, the feet of pairs of holders swinging on the same pin, the feet of one holder of one pair being arranged on the pin between the feet of the other holder of the pair. The holders of one pair are interlaced between the holders of another pair. Compared with th usual drying conveyors in which the distance of the pins equals the distance of the center lines of the work piece holders, a drying conveyor constructed according to the invention may contain twice the number of holding members. Therefore, with a conveyor drum having half the diameter of the usual drums the drying process may be effected within the same drying time. This reduces the height of the entire machine so much that all other operations can be performed at a distance from the floor allowing supervision without the aid of running boards, steps or the like.

A further improvement provided by the invention is the removal of the work pieces from the work piece holders of the drying conveyor by transport means having projections engaging the fold of the bottom flap, the work pieces being held against the projections by a rotating rubber brush acting in a direction opposite to the travel direction of the envelopes before they arrive at the device for folding the closing flap. Therefore no adjustment of individual work pieces is required.

The drawings show by way of example a machine serving for the manufacture of envelopes and flat bags with inner and outer prints and with gummed closing flaps.

Figs. 1 to 3, if arranged dot and dash lines, show a vertical longitudinal section through the machine.

Fig. 4 illustrates two work piece holders with inserted work piece in plan view.

Fig. 4a is a side View of a plurality of work piece holders.

Fig. is a top view of an uncoiled web of work material showing individual phases of the manufacture of envelopes.

Fig. 6 illustrates an uncoiled web and the individual phases of producing a flat bag.

According to Fig. 5, the operations follow each other in the following sequence:

I. Inside printing (cylinder I3).

II. Outside printing (printing device 22).

III. Outside printing (printing device 23).

IV. Cutting out of the folding seams (cutter 28).

V. Longitudinal preliminary breaking (roller 4i).

VI. Laying down of the folding seams (guides 42,

43, rollers 44-46).

VI5I.9)Gumming of the folding seams (summer VIII. Transverse preliminary breaking (breaking knife 66). IX. Form and cross cutting (knives 19 and 80). X. Folding the bottom flap (folding knife 89). XI. Gumming the closing flap (gummer 91).

XII. Folding the closing flap (foldin means side by side along the 1 Flat paper bags are made by the same sequence of operations which are illustrated in Fig. 6 in juxtaposition to Fig. 5.

The paper web I or a strip of another material to be worked is fed from the supply roller 2 arranged between the two brackets 3. The correct position of said roller is adjusted by means of a controlling wheel 4, a brake and guiding rollers 5-8, a tiltable roller 9 being provided for tightening the web I. The web runs in the direction of the arrows along to the dash-line. The first operation during the manufacture of envelopes or flat bags is the inside and outside printing. Three aniline printing devices are sufficient for normal manufacture. The first printing device produces a printed design on that surface of the web which later on is the inside surface of the finished work piece. Between the guiding rollers I, 8', the counter-pressure cylinders l0, ll, l2 of the printing devices are supported by the frame Ul or the link bracket ll respectively. The plate cylinder [3 of the printing device receives the ink through the transfer cylinder M from the dipping roler l5 engaging said transfer cylinder and dipping into the ink fountain It. The plate cylinder I3 and the dipping roller ii are supported by the link brackets [8, I9, guided by the guiding means H. The transfer cylinder I4 is supported by eccentric bushes of the pair of levers tiltable around bolts. Hereby a very fine adjustment of the ink supply is possible. Besides, the inking device is provided with a readily removable apparatus, not shown, centrally actuated by a rack gear for preventing sticking of the plate cylinder to the paper web. The two next ani

ine printing devices

22, 23 are of an equal construction and produce the print on the outside surface of the web in two colours. To balance the printing distance between the different printing devices a register roller 24 is supported by the lever 25 affording change of the printing relative to the travel direction of the work piece by means of worm gears during operation of the machine. After having passed through the three printing devices of which only one or two may become operative if desired, the web of paper or any other suitable material is fed to the pair of cutting out rollers 25, 21 for preparing the folding seams on both sides. The knife roller is solidly supported by the bracket UI and is driven by the main shaft 50 through shaft 58. On the body 2'1 of the knife roller one or two cutting out knives are fastened by screws, the knives individualy consisting of one piece. The number of revolutions of the knife roller is determined by t-.e toothed wheel 29. The counter-roller 28 provided with notches is supported by a pair of levers 30 tiltable around the axis 3| which may be adjusted corresponding to the thickness of the material by a worm wheel segment 32 and. a worm. The yielding roller 33 supported by the pair of levers 34 tiltable around the axis 35 prevents tearing of the thin material during the cutting operation. The waste paper is sucked off by a strong air current produced by the ventilator 35 and is transported through suction pipes 31 to a container 38. The ventilator is driven by the intermediate shaft 49 by means of a belt. The intermediate shaft 49 is directly driven by an electromotor controlled by a push button switch, not shown. The cut out paper web is now guided around the guide roller 39 to the preliminary breaking rollers 4| (Fig. 2) coacting with the rubber coated lower rollers 4!) where the folding seams are preliminarily broken in the longitudinal direction of the web. The folder 42, lower guides 53 and upper guides 43 turn th folding seams completely over. To ensure the entering of the cut out and preliminarily broken web into the guides 42, 53 an adjustable and tiltable guide roller 4 3 is provided. The final folding of the folding seams is made by folding rollers it resiliently supported by levers and having bulged surfaces cooperating with roller d5. The pressure of the folding rollers lt may be adjusted. The speed of rotation or the length of the supplied portion of the web required for the manufacture of one work piece is determined by a speed change wheel W arranged on the additional shaft ll. The driving wheel 48 of this shaft is driven by the toothed wheel 65) of the main shaft 55 sup ported by the lower frame U2. The numbers of revolution of these two shafts are proportional to each other or are equal so that one length of a work piece is fed during each complete revolution of the additional shaft 4?. The delivering roller 5i and the feed rolls 52 destinated to uncoil the necessary length of the web i from the supply roller 2 are driven by an intermediate wheel 53 supported by an adjustable member 5a and rolling on the pitch circle of the change speed wheel W. The greater or smaller the diam eter of the said pitch circle is the greater or sma ler is the speed of rotation of the delivering roller 55 and of the feed rollers 52 and consequently also the fed length of the paper web. The feed rolls 52 are driven by the delivering roller 5! and are yieldingly supported by a pair of levers 55 tiltable around the axis 56. The printing devices are driven by the roller 5i through a toothed wheel 5! and a shaft 5'? to avoid register differences. Now, the web of paper or any other suitable material is further delivered by the feed rolls Si, 63. The feeding speed. between the pair of rollers 5!, 52 and the pair of feed rolls ill, 68 is so adjusted that the web is tensioned between these two pairs of rollers. While the work pieces are running over the delivering roller til the adhesive substance is applied to their folding seams lying inside and being folded down, by means of the rotating gumming segments 5Q. These segments 59 takethe adhesive substance from the removable container Gil by means of the drawing roller 6!. The segments 59 are adjustable with respect to their distance in conformity with the different widths of the work pieces; their number of revolutions is determined by the speed change wheel W. One pair of gumming segments suffices for all sizes. The thickness of the gum layer finely adjusted by excentrically supported bushes on shaft 52 and by the scraper 6 5. After the web has passed by the feed rolls 5!, 52 the upper roller together with the rubber coated lower roller 6Q preliininarily break the fold of the bottom flap. The 7 upper roller 65 carries preliminary creasing knives 65 extending in the axial direction and be ing adjustable with respect to their distance corresponding to the different sizes of the work pieces. After initial adjustment, the upper roller 55 is left alone to avoid additional adjustment of the creasing knife 65. The roller E5 is provided with a differential gear enabling a fine adjustment of the preliminary creasing action during operation of the machine. For testing the spacing of the prints of the preliminary folds before effecting cutting to shape or cutting off, a conventional testing device is provided between the feed rolls 5|, 52 and iii, 58,. It comprises a test lamp es as a light source and a photoelectric 6 cell 10 encased in a rotating cylinder ll having a window 12. The cylinder H is driven by the upper roller 55 through toothed Wheels l6 and 55' and runs synchronously with the main shaft 5t. If the printing mark of the paper web 5 coincides with the window 72 in cylinder ll after every revolution and if therefore the light ray of the light source passing through the window at the same moment does not actuate the photoelectric cell it! the feeding speed of the web is equal to the feeding speed predetermined by the speed change wheel W. If, however, the distance of the printing marks changes, the light ray energizes the photoelectric cell iii which engages an accelerating coupling it, which is slidably connected with the delivery roller 5 i for temporarily changing the feeding speed until the window it again coincides with a printing mark on the paper web during the rotation of the cylinder ll The accelerating coupling "if; is driven by a differential gear not illustrated and known per se. After the printing and the preliminary folding of th bottom flap have been tested, the form cutting or cross cutting operation may begin. The paper web I is fed by the feeding rolls ill, it to the delivering rollers i l, '55 via the cutting rollers l5-3l. The feeding speed between rollers and l4, i5 is so adjusted that the paper web is tensioned between these two pairs of rollers. The form cutting and cross cutting operation of the individual lengths of work pieces is done by a rotating upper roller ll carrying a form cutter 19 or a slitting knife 88 engaging a stationary lower knife "it. The knives work scissorslike, i. e., the web is not cut off all at once over its whole width but the lower knife it has a certain adjustable inclination relative to its carrier iii corresponding to the width of the web or the feeding speed of the work material. For a form cut-- ting operation a resilient one-piece form knife 'IQ is mounted, which is relief-milled in such a way that its cutting edge rolls on the lower knife 16. The rotational speed of the form knife ill is accelerated at the cutting moment and synchronized with the feeding speed of the paper Web by means of a cam or the like. The cutting roller i? carrying th form knife re runs synchronously with the main shaft 5% and its diameter is not changed when the size of the work piece is altered. For the cutting operation a known adjustable upper knife $63 is screwed on the cutting roller Tl. The pair of rollers it. i5 is the last pair of rollers the feeding speed of which is determined by the speed change gear W on the additional shaft ll. The upper roller "IE5 may be alternately raised and lowered. Both rollers :4 and i5 feed the work piece to the pair of rollers 8!, 82 which advance the severed pieces. Since the upper roller 32 of this pair is constructed as a segmental roller the work piece is not seized in the first instance. Only at moment when the cutting operation is finished, advancing is effected by the segmental roller 8 at an increase speed. The increased speed of the segmental ro ler 82 is equal to the s ed f the main shaft Ell. After the work r e b securely seized by the segmental roller t2 the upper roller "l5 raises to avoid displacement and tearing. The segment roller 32 and the following working rollers feed one blank at every complete revolution and therefore their diameter must be adapted to the greatest work piece to handled by the machine. The working rollers are driven by a shaft S. Now a pair of rollers 63, 84 receives the work piece andfeeds to the next pair of rollers 85, 86. Between these two pairs of rollers 83, 84 and 85, 86 the bottom flap of the work piece lying in front in the feeding direction is upwardly guided along its preliminary fold by means of a tiltable plate 8'5. To avoid disturbances during the upward guiding of the bottom flap by the roller 85 an adjustable guide plate 88 is provided. After having been upwardly guided the bottom flap of the work piece is conducted by the tiltable folding blade 89 engaging the crease of the bottom flap, between the pair of rollers 85, 35 by which the fold is pressed on and the bottom flap glued. Two further pairs of rollers 90, 9| and 92, 03 receive the work piece and advance it between the pair of rollers 94, 95, the upper roller of which is provided with an adjustable segment 95 advancing the work piece by seizing the glued work piece portion lying in front in the feeding direction, and which is further provided with an also adjustable gummer 91 adapted to apply the adhesive substance onto the closing flap lying in the rear in the feeding direction, while the lower roller 94 carries corresponding counter-segments. From the gum container 98 the gum is applied to the gummer 91 of the roller 95 by means of the drawing roller 89 and the gum applying roller I532. To avoid direct applying of gum by the gummer 91 of the roller 95 onto the counter-segment of the lower roller 94 if no work piece is present, devices, known per se, such as a magnetic controlling device IOI are provided by which the lower roller is automatically lowered and disengaged from the upper roller esides, the gum applying roller I is intermittently raised and lowered so that it only engages the gummer t? but not the advancing segment 95 of the rol er 95 for keeping the last mentioned segment free of gum. The work piece leaving the pair of rollers 94, 95 and having its closing flap opened and gummed is received by a pair of rollers I62, we, the upper roller I03 of which is intermittently raised and lowered to avoid coming into contact with still moist gum of the closing flap. The pair of rollers I02, I03 guides the work piece to the work piece holder which holds the work piece whi e it is passed through a dryer for drying the gum applied to the closing flap. Referring more particularly to Figs. 3 and 4, the work piece holders operate as follows:

On the lower frame mounted supports I04 for a shaft I05. The con veyor drum I00 consists of two wheels I06 held together by connecting rods I01. The drum I0? carries a plurality of work pieces. The frames I08 (Fig. 4:) are provided with guiding notches N to prevent sagging of the work piece holders when entering and leaving the conveyor drum. The grooves are deep and broad enough to allow free movement of pins H2. Each work piece holder lee-4 I2 shown in Figs. 4 and 4a in a plan and a side view, respectively, and in an en arged scale, consists of the foot connected with a platform having a rigid plate-like upper part [I0 and the slightly yielding lower part Ii rivetted to the said upper part. The individual work piece holders are connected pairwise by pins i I2 and form an endless link chain tensioned by screws H3. Due to the yielding engagement of the yielding lower part I I I of a work piece holder with the rigid upper part IIiI of the neighbouring work piece holder the chain is gradually closed and compressed when it moves from a curved into a relatively straight portion of its path. The surface being under pressure is indi- U I of the machine are cated in Fig. by dotted lines outlining a work piece, the gummed portions of which are indicated by hatching. The foot of each holder has two diverging prongs and a pin H2 extends through the end of each prong, the prongs of the foot of one holder being individually interspersed between the prongs of the feet of the adjacent holders. The distance between two pins H2 is twice as great as the distance between the cen ters of two neighboring work piece holders. Two different holders are connected with each pin, the feet I09 of one holder being arranged inside the feet I09 of the other holder connected with the same pin. The holders connected with one pair of pins are individually placed between the holders connected with the neighboring and interspersed pins (Fig. 4a). The toothed shaft II5 supported by stationary bearing I I4 on the lower frame U3 of the machine advances the chain and places the work piece holders I09--II2 in the proper position for receiving the work pieces leaving the pair of rollers "12, I03. The pitch of the teeth on shaft H5 or the distance between the centers of the work piece holders II9-I I2 is so chosen, that the latter open only so far, that the longest work piece to be worked may surely enter. The work pieces are fed to the work piece holders I09-I I2 in the following way:

The transporting or loading chains I I9 receive the work piece from the pair of rollers I02, I63. The transporting chains H0 are guided each over a set of chain wheels II5-II8; they are driven by the lower roller I02. The chains II!) advance always in the moment in which one of the work piece holders arrives in a position in which the upper surface of the upper part III) lies somewhat below the advancing path of the work piece formed by the transporting chain I I9. The work piece is stopped when the bottom flap B of the work piece leading in the transporting direction reaches the adjustable abutments I20. The toothed shaft I I5 is continuously driven with such a speed that during each working of a work piece by the machine the circumference of the transporting drum I06 rotates for an amount corresponding to the distance between two consecutive work piece holders. At a short distance from the free ends of the work piece holders I09-I I2 a heated air channel T is arranged concentrically to and around the transporting drum I06 supplying heated air from any suitable source, f. i. a ventilator V connected with an adjustable electric heater H, for drying the adhesive substance on the closing flaps. The wall of the heated air channel T facing the transporting drum I05 is provided with openings 0 through which the heated air is blown against the work pieces in the work piece holders.

For removing the work pieces from the work piece holders l09ll2 the following device is provided.

The toothed shaft I15 supported by the lower frame U3 of the machine controls the removing operation of the work pieces from the link chain of the drying device. The two toothed shafts I I5 and H5 are commonly controlled by a transmission gear 15 indicated by dot and dash circles. If a work piece holder carrying a work piece arrives below the lower run of the conveyor chain I21 after having passed the drying device during the rotation of the transporting dnim its in the clockwise direction, the endless chain of holders begins to open so that the work piece lies freely on the upper part III]. In the same moment a cam I26 of the chain I21 engages the bottom fold B of the work piece and pushes the latter out of the holder [09-4 l2. The conveyor chains are fastened on the extension arms of the intermediate members I22. They consist each of a set of chain wheels l23-|25 over which the chain I 2'! runs which is provided with transporting projections i125. The chain I2! is driven by the shaft I28 through the folding tongs cylinder I29. The work piece leaving the work piece holder in a position in which the closing flap lies in front is advanced by the folding tongs cylinder E29 and the folding knife cylinder its until the folding edge of the closing flap is reached. The closing flap of the Work piece is folded by the folding knife i3l entering the opened tongs and is folded down by the pressure roller 232 coated with rubber. The lower run of the chain i2? and the upper edge of the folding tongs cylinder I29 must be arranged on the same level. For this purpose an adjustable plate hit is mounted between the lower frames U3, said plate carrying the intermediate members E22 supporting the folding cylinders I29, I30. ihe folding cylinders I29, it!) are driven by a shaft [3% driven by the main shaft 50. For correct seizing of the folding edge of the closing flap of each work piece leaving the work piece holder by the folding knife iii! of the cylinder I30 a sucking rubber brush E33 is provided rotating opposite the feeding direction. Ihis produces a braking effect whereby the Work piece is held in correct engagement with the projections 526 of the chains ml. The rubber brush is driven by the folding tongs cylinder I29. The completely folded work piece is guided to conventional conveyor worms 35 and is laid down onto assembling bars ass and the table I38. The rotation of the transporting worms I35 is so timed as to assure individual free entry of consecutive work pieces. The transporting worms are driven by the toothed wheels. 55, 3? shown in the drawings by dot and dash lines. The assembling bars 238 may be adjusted with respect to their height above the floor by a rack M and toothed wheel Mi for reducing the height of fall of small work pieces. By a known counting device not shown in the drawing the work pieces are automatically counted in an aligned pile i351 where each twenty fifth or fiftieth Work piece projects, a braking member lad preventing the pile to fall down in the transporting direction. In order to remove gummed work pieces from the drying device at the end of a working period or for longer rest periods a coupling Ki is provided for disconnecting the operation of the drying device and of the last folding means. This apparatus is driven by the toothed wheel 49'.

The machine described above serves for the manufacture of work pieces provided with inside and. outside prints and gummed closing flaps. If fiat bags are to be manufactured having open and not gummcd closing fiaps which may be preliminarily creased or not, first the drying device is put out of action by means of a coupling E; mounted in the frame U3. A guide means having a deflecting bar M2 of triangular cross section is clockwise rotated so that the left edge of bar Hi2 is upwardly moved and the work pieces are downwardly deflected and are seized by the transporting roller I43 and are conducted to the further pairs of transporting rollers l44--i48. The folding cylinders I29, I36} now serving only as transporting rollers receive the work piece and working machine without interrupting conduct it to the transporting worms I35. Hereby the open closing flap is upwardly directed so that the work pieces may be piled freely. The closing flap may be preliminarily creased, if desired, by a second adjustable creasing knife 66 of the upper roller 65 so that both preliminary creasing operations are made by the upper roller 65.

Having thus particularly described and ascertained the nature of my invention and the manner in which it is to be performed, what I wish to have covered by Letters Patent is:

1. A machine for making envelopes and flat bags from a continuous Web of envelope material, comprising means for continuously advancing the web of envelope material, periodically effective printing means disposed along the path of the running web for printing on the latter, periodically effective cutting means adapted to receive the running Web from said printing means and adapted to cut lateral marginal portions from the web, leaving folding seam portions on the web, seam folding means adapted to receive the running web from said cutting means and to fold the seam portions upon the web, first gumming means adapted to receive the web from said folding means and to gum the folded seam portions, severing means adapted to receive the running web from said first gumming means and to sever individual work pieces from the running web, folding means adapted to engage the work pieces, one after another, as they come from said severing means and to individually fold a part of the individual work pieces onto the gummed seams thereof for forming a pocket, second gumming means capable of being operatively or inoperatively conditioned and adapted to engage the work pieces, one after the other, as they come from said last mentioned folding means and to gum marginal portions of the unfolded part of the work pieces, which part forms the closing flap of the envelope, dryer means, an endless conveyor means having a run disposed inside and travelling through said dryer means and having a run disposed and travelling outside of said dryer means, loading means disposed between said second gumming means and the run of said conveyor means outside of said dryer means, said loading means being adapted to receive the work pieces from said second gumming means and to load the work pieces onto said conveyor means, removing means disposed adjacent to said conveyor means where the conveyor means leave said dryer means and adapted to remove the dried work pieces from said conveyor means, a pair of laterally adjacent rollers disposed adjacent to said removing means and adapted to receive the work pieces coming from the removing means between the rollers, transport means for the work pieces interposed between said second gumming means and said pair of rollers and by-passing said loading means, said conveyor means and said removing means; and selectively operative guide means interposed between said second gumming means and said loading means and adapted to selectively guide the work pieces coming from said second gumming means either toward said loading means in the operative condition of said second gumming means or toward said transport means in the inoperative condition of said second gumming means.

2. A machine as defined in claim 1, comprising closing flap folding means removably connected with said pair of rollers.

3. A machine as defined in claim 1, said second ll gumming means comprismg removable applying means.

4. A machine according to claim 1, comprising a power shaft, Work piece advancing means adapted to advance the severed work pieces, first drive means interposed between said power shaft and said work piece advancing means and adapted to drive the latter synchronously with said power shaft, change speed means driven by said power shaft, and second drive means interposed between said change speed means and said printing means, said seam folding means, said first gumming means, and said severing means.

5. A machine according to claim 1, said endless conveyor means comprising a drum, a plurality of work piece holders, each holder having a platform adapted to support a work piece, and a foot connected with the platform, pins pivotally conmating the feet of pairs of said holders to form a chain which is looped around said drum, stationary guide means adjacent to the ends of said drum and engaging said pins, said guide means forming curved path portions of relatively small radius adjacent to said loading means and adjacent to said removing means, efiecting spreadof said platforms thereat to receive and discharge -a work piece.

6. A machine as defined in claim 5, said guide means forming a circular path portion of relatively large diameter around said drum, each of said platforms comprising a rigid plate-like upper part and a yielding lower part rigidly connected with said upper part, the work pieces being individually laid on said upper parts and being individually abutted by the yielding lower parts of the adjacent holders when the chain formed by the feet and pins of said holders travels along said circular path portion.

'7. A machine as defined in claim 5, the foot of each holder having two diverging prongs, said pins extending through the end ofsaid prongs, there being two parallel pins to each holder, the prongs of the foot of one holder being individually interspersed between the prongs oithe feet of the adjacent holders.

'8. A machine as defined in claim '5, said removing means comprising a conveyor chain having a run substantially parallel to the platform of the holders arriving at the removing means, said last mentioned run being moved in a direction away from the foot of the work piece holder arriving at said said removing means, a cam mounted on said chain and being adapted to engage the bottom edge of the Work piece on the platform, and a rubber brush disposed adjacent to said run of said chain and adapted to frictionally engage the work piece engaged by said cam, said brush being moved in opposite direction to the direction of movement of said chain for pushing the work piece against said cam.

9. The combination with a machine for making envelopes and fiat bags, which machine comprises means for continuously advancing a web of envelope material, means for printing on the running web, means for cutting folding seams, means for folding and gumming said seams, means for severing individual work pieces from the running web and simultaneously forming the closing and bottom flaps, means for closing the bottom flaps, means for gumming the closing flaps, drying means and envelope conveyor means passing therethrough, and means for piling the finished envelopes: of means for disabling the means for gumming the closing flaps and selectively operative deflecting means interposed between the means for gumming the closing flaps and the drying means and adapted to deflect the work pieces to by-pass the drying means and pass to the piling means when the means for gum ming the closing flaps has been disabled.

HANS HEITMANN.

References Cited in the file of this patent UNITED STATES PATENTS