US3354798A

US3354798A - Method of making envelopes

Info

Publication number: US3354798A
Application number: US477558A
Authority: US
Inventors: Winkler Richard; Dunnebier Kurt
Original assignee: Individual
Current assignee: Individual
Priority date: 1964-08-20
Filing date: 1965-08-05
Publication date: 1967-11-28
Anticipated expiration: 1984-11-28
Also published as: DE1436853B2; GB1064612A; DE1436853A1

Description

Nov. 28, 1967 R. WINKLER ETAL 3,354,793

METHOD OF MAKING ENVELOPES Filed Aug. 5, 1965 Lf" l\ .-Q N DEW f 0u L 3 K H nl 0 .ag m N Q8 En@ @a a N@ -Q u D N Ll. II t\ NN N y iQ. N M

N N 1 N Q .13 N LL United States Patent O 3,354,798 METHD F MAKING ENVELPES Richard Winkler, Enrgernieister-Wink-Strasse, Rengsdorf,

Germany, and Kurt Diinnehier, Am Birken-thang, Gladhach, Germany Filed Ang. 5, i965, Ser. No. 477,558 Claims priority, application Germany, Aug. 20, 1964, W 37,416 14 Claims. (Cl. 93-63) The present invention relates to a method of manufacturing envelopes, especially open-end envelopes in continuous operation, and more particularly, to a method of manufacturing in continuous operation envelopes from blanks which including bottom, side and closure flaps consist of a single piece cut from a continuously fed web, such as a paper web.

There are known several methods of producing envelopes from one or also two continuous webs by gluing the webs along both lengthwise sides thereof. With these known methods, as many operational steps as possible are carried out on the continuous web or webs before the more or less completed envelopes are separated from the web.

To produce envelopes of different lengths and widths preformed side flaps, bottom flaps and closure flaps from a continuously fed web, cutting rollers of a specific diameter must be used for the length of the different envelopes to be produced, since the circumference of the cutting rollers must equal the development of the blank for the respective envelope. The same is true for cutting window openings into the continuously fed web from which the blanks for making the envelopes are cut. The inventory of cutting rollers and the cutting tools proper mounted thereon which must be maintained for producing envelopes of different lengths is expensive and the time required for resetting a machine from one length of envelopes to another length is considerable. Accordingly, unless the envelope machines are used for producing a high run of only a few dimensions of envelopes, machines of this kind are not economical in spite of the saving of paper and in punching or cutting operations when a continuous web is used as starting material.

It is -a broad object of the invention to provide a novel and improved method of producing at bags or envelopes, particularly large sized envelopes in a more economical fashion than is possible with methods for the purpose as heretofore known.

The aforementioned object, feature and advantage and other objects, features and advantages which will be pointed out hereinafter are -attained by feeding a web at a uniform rate of speed past a cutting device which cuts the web crosswise into successive rectangular pieces. Each of these pieces constitutes a preliminary or raw blank, the width and length of which correspond substantially to the width and length respectively of the envelope to be produced. The blanks are accelerated to a higher rate of travel, preferably to a speed such that one envelope blank is cut per revolution of the cutting rollers. The moving blanks are subjected one by one to further cutting operations until the desired final outline of the blank is obtained, that is, a blank defining the required side aps, a bottom fiap and a closure fiap. The flaps are then pref folded, coated with adhesive and nally folded upon one another.

It is preferable to change the direction of travel of the blanks after the fiaps thereof are cut so that the initial lengthwise orientation of the blanks remains unchanged for -a purpose which will be more fully explained hereinafter.

It is also an object of the invention to provide a meth- ICC od which permits the use of different types of adhesive and also of different foldings of the bottom and closure flaps.

The method of the invention will be more fully explained in connection with the accompanying drawing which shows diagramm-atically flow sheets for producing single piece envelopes.

In the drawing:

FIG. 1 is a flow sheet showing the manufacture of onepiece envelopes beginning with the feeding of a continuous web and ending with completed and stacked envelopes;

FIG. 2 is a modification of the sequence of the steps required for gurnrning the bottom and closure flaps of the envelopes;

FIG. 3 is another modification 0f the operational steps required for gumming the bottom and closure fiaps; and

FIG. 4 is a modification of the path of travel of the blanks during the processing thereof.

The invention provides for applying a single gluing of the envelopes along the mid-line thereof and it also provides for a single lateral gluing of the mid-portion of the envelopes. It further discloses three different methods of gumming and of folding the bottom and closure flaps of the envelopes.

It should be understood that the tools required for cutting the blanks, applying adhesive thereto, folding the blanks and stacking the finished envelopes do not constitute part of the invention. All these tools should be visualized to be conventional and are hence not illustrated or described in detail.

Referring now to FIG. 1, the flow diagram shown in this figure illustrates a continuous web 1, such as a paper web, which is supplied from a supply reel (not shown) and travels along a rectilinear path in the direction of the arrow at a predetermined uniform speed. The width B of the web should be visualized as corresponding to the width of the finished envelope to be produced. At a selected point of travel, cross cuts 2 are made by a suitable cutting device, such as a rotary cutter, to produce successive rectangular preliminary or raw blanks 3 with the length L. The blanks 3 are immediately accelerated to the working speed of the envelope making machine Whereas the length L of the blanks corresponds to the lower rate of travel of web 1 per operation of the cutting tools. As la result of the yacceleration of blanks 3, lengthwise gaps D are formed between each two blanks.

Prior to the cutting of the web, for instance, in the position indicated by xx, the web may be printed on one or both sides. Since the rate of travel of the web is equal to the length L per operation of the cutter, the printing rollers must have a diameter correlated with the length L unless it is desired to cover the entire surface of the web with print. However, this limitation which must be observed to obtain a Asuitable diameter of the printing roller is more than balanced by the long drying path which is provided for the print on the moving web.

In the station or position 5, marginal portions 8 are cut off from the blank by suitable rotary cutting tools to define a bottom flap 6 and a closure flap 7. The blank has now its final outline.

The outline of the blank as illustrated in position 5 is designed for making envelopes glued at the mid-line thereof. In the event envelopes glued along a side are to be produced, the blank must be cut as it is shown in the station or position 5', that is, the cut-out portions 8 are shaped to produce the bottom flap 6 and the closure fiap 7. Both shapes of the blanks may be cut with the same cutting tools.

In the station or position 9, preliminary fold lines 10 are formed by suitable folding devices, such as a rotary f3 D straight scoring means and an elastic counter roller. The scoring means and the roller are adjustable in reference to each other. The preliminary fold lines 1t) serve to facilitate the later final folding of the flaps.

In the station or position 11, each blank is turned Athrough an angle of 90 in reference to the initial path of travel of the web. In the event lack of space makes it difficult to provide an angular path of travel in the enyelope making machine, the blanks themselves are turned through an angle of 90 by means of a suitable device,

such as a turn-table as it is indicated at station or position 11' in FIG. 4, but continue along the initial path of travel.

Otherwise, the processing of the web and later on of .the blanks is carried out in the arrangement of FIG. 4

and the closure flaps thereof.

lIn the station or position 14, preliminary fold lines 1S are made to define two

side flaps

21 and 22. These fold Vlines for the side aps may be formed in the same manner as has been described for the fold lines of the bottom flap and the closure flap in connection with position 9. However, vit is also possible to produce fold lines and 15 in immediate succession, that is, the

positions

9 and 14 may be adjacent to each other.

In lthe station or position 16, one or several windows r17 are cut into the blank by suitable rotary cutting means.

In the station or position 18, windows 17 are covered by a suitable transparent foil of film 19 which is glued to the `blanks in a conventional manner.

The

positions

16 and 18 may be omitted if envelopes fwithout ywindows are to be produced. In an envelope making machine for carrying out the method of the inyention, the tools required in

positions

16 and 13 are preferably arranged as optional or detachable tools.

In the station or position 20, the bottom Vap 6 and theclosure flap 17 are rst folded along the preliminary fold linesfand arethen opened again.

yIn the station or position 23, the leading side flap 21 is folded over as shown along its fold line by a suitable folding tool.

In the station or position 25, a stripe 26 of a suitable adhesive is applied to the trailing side flap 22.

In the station or position 27, the gummed side flap 22 4is folded back upon .the previously folded side flap 21 so that the side aps are now adhered to each other.

After folding and gumming of the two side flaps, the rate of travel of the blanks is preferably reduced to about half the speed bycorrespondingly reducing the diameter of the transport rollers of the machine.

In the station or position 28,

stripes

30 and 31 of the adhesive are simultaneously applied to the bottom flap and the closure flap.

In the station or position 29, the bottom flap 6 is folded back upon the previously glued together side flaps 21 and 22, but the closure ap 7 is left open.

The ,now nearly completed envelope is guided through a drying zone T for drying the stripe of adhesive applied vto the openv closure flap 7. The envelope while travelling through the drying zone is preferably held by suitable conventional tools, such as springy grippers.

In the station or position 32, the closure flap 7, the adhesive on which is now dry, is also folded over and the then finished envelope is stacked in the position or station 33 on the table of the machine.

T he aforedescribed method of the invention has the advantage that for producing envelopes of different lengths the tools required for carrying out the aforedescribed operations-need not to be changed.

In the event envelopes of different widths are to be produced, it is merely necessary to set upon the rollers and carries remaining in the machine, tools which have the appropriate width for carrying out the aforedescribed operations in

positions

5, 25 and 28. If the dimensions of the windows are to be changed, a suitably dimensioned tool in the window cutting station 18 is, of course, also necessary.

Another advantage of the method of the invention is that the bottom flap and the closure flap 7 are always oriented crosswise of the lengthwise extending fibers in a paper web. As a result, the bottom flap and the closure ap tend to curl or wrinkle less when the adhesive is applied thereto than they would if the flaps extend parallel to the direction of the fibers.

Finally, the orientation of the finished envelopes lengthwise of the web permits the manufacture of lengthwise striped envelopes in an economical fashion by using a lengthwise striped paper web. Lengthwise striped openend envelopes are preferred by postal authorities in many countries.

FIG. 2 shows the application of adhesive to the bottom flap and the closure flap of so-called self-sealing envelopes and some of the subsequent operational steps.

In the station or position 28', a stripe 39 of dextrin or other suitable natural or synthetic gum is applied to the bottom flap 6a and a latex stripe 34 to the closure ap 7a. A corresponding latex stripe 35 is applied to the main portion of the envelope blank crosswise to the length thereof.

In the station or position 29', the bottom ap 6a is folded back to be glued to the side flaps which are earlier folded as described. The envelope blank is now guided through a dry Zone T to the station or position 32'. The closure ap is not folded in the position 32', that is, the finished envelopes are delivered to the station or position 33 to be stacked on the table of the machine with the closure flap still open.

FIG. 3 shows a flow diagram for the gumming of the bottom and closure flaps and some of the subsequent operational steps for producing envelopes to be used for printed matter.

Envelopes for such use require that the bottom or closure flap can be opened and reclosed by the postal authorities for inspection. To permit such opening and reclosing, the bottom flap 68 is coated with a special adhesive which permits a repeated adhesion and reopening in dry condition. Suitable adhesives for the purpose, generally having a latex base, are well known and generally available in the market and do not constitute part of the invention.

In the station or position 28", a stripe 51" of dextrin or similar material is applied to the closure ap 7b and simultaneously a stripe 36 of the aforementioned special adhesive is applied to the bottom flap 6b and a stripe 37 of the same special adhesive is also applied to the mid or main portion of the blank.

The now nearly completed envelope is subsequently guided through a drying zone T to a station or position 32 with the bottom flap and the closure flap left open.

In the position 32, the bottom flap and the closure flap are both folded back whereby the bottom iiap 6b, which is coated with the special adhesive, is adhered to the side flaps.

Finally, the finished envelopes are stacked in the position 33 on the table of the machine.

The concept of the method according to the invention is not limited to the aforedescribed specific sequence of operational steps for producing envelopes with gluing of a single side iiap. The sequence of the operational steps following the separation of the rectangular blanks 3 from web 1 may be changed if desirable without departing from the basic concept of the invention. Furthermore, the concept of the invention also includes the manufacture of differently shaped envelopes, for instance, of envelopes having bOth side flaps glued.

What is claimed is:

1. A method of producing single piece envelopes in continuous operation, said method comprising the steps of feeding a continuous web of uniform width along a predetermined path and at a predetermined speed, making uniformly spaced crosswise cuts through said moving web, each of the cut-off web pieces constituting a preliminary envelope blank, accelerating each of said blanks to a higher predetermined speed causing a lengthwise spacing of said blanks along said path, cutting olf marginal portions of each moving blank to define side, bottom and closure flaps, forming preliminary fold lines along the base lines at which said iiaps are joined to the main Ibody of the blanks, applying adhesive at least to one of the side flaps and to the bottom liap on one side thereof, and folding the side iiaps and the Abottom iiaps upon one another along said fold lines.

2. The method according to claim 1 and comprising the step of cutting at least one window in the main body of successive moving blanks.

3. The method according to claim 2, wherein said Window is cut subsequent to the forming of the preliminary fold lines in the aps and prior to the folding of the flaps.

4. The method according to claim 1 and comprising the steps of cutting at least one window in the main body of successive moving blanks, and covering the window in each blank with a transparent foil.

5. A method of producing single piece envelopes in continuous operation, said method comprising the steps of feeding a continuous web of uniform width along a predetermined path and at a predetermined speed, cutting said web crosswise at equal spatial intervals, each cut-off web piece constituting a generally rectangular envelope blank, accelerating the successively formed blanks to a higher feed speed than the feed speed of the continuous web to cause lengthwise spacing of the moving blank-s, cutting off marginal blank portions at the crosswise edges of each Iblank to define side fiaps, a bottom iiap and a closure flap, scoring said flaps of each blank at the junction lines thereof with the main body thereof to form preliminary fold lines, applying adhesive to at least one of the side flaps, the bottom and the closure flap on one side thereof, folding the side aps and bottom aps upon one another along the preliminary fold lines thereof to adhere said aps to each other, drying the adhesive applied to the closure ap, and folding the closure ap along the prelllilrninary fold line thereof upon the main body of the bla 6. A method of producing single piece envelopes in continuous operation, said method comprising the steps of feeding a continuous web of uniform width .along a predetermined path and at a predetermined speed, cutting said web crosswise at equal spatial intervals, each cut-off web piece constituting a generally rectangular envelope blank, accelerating the successively formed blanks to a CII higher feed speed than the feed speed of the continuous web to cause lengthwise spacing of the moving blanks, cutting off marginal blank portions at the crosswise edges of each blank to define side flaps, a bottom flap and a closure flap, scoring the closure iap and the bottom iiap of successive moving blanks at the junction lines of said iiaps with the main body of the blanks t0 form preliminary fold lines, changing the positioning of the blanks in reference to the initial positioning of travel thereof, scoring the side aps of successive moving blanks at the junction lines of said side aps With the main body of the Iblanks to form preliminary fold lines, coating at least one side iiap of successive moving blanks with adhesive, folding the side flaps of successive moving blanks upon each other to adhere the same to each other, coating the bottom and the closure flaps of successive moving blanks with adhesive, folding the bottom iiap of successive moving blanks upon the folded and Aadhered side flaps, and letting dry the adhesive coating on the closure flap.

7. The method according to claim 6, wherein successive blanks are first guided along a first substantially rectilinear path of travel and then, without change in axial orientation of the flaps, along a second substantially rectilinear path of travel dening a substantially right angle with the first path thereby turning each blank through an angle of in reference to the initial positioning thereof.

8. The method according to claim 6, wherein successive blank-s are each turned through an angle of substantially 90.

9. The method according to claim 6 and comprising the step of aligning each blank after changing the position of orientation thereof in a predetermined position in reference to the direction of the path of travel thereof.

10. The method according to claim 6, wherein at least one flap of successive moving Iblanks is coated with a self-sealing adhesive to permit reopening of folded-back flaps.

11. The method according to claim 10, wherein the closure ap of each successive blank is coated with a self-sealing adhesive.

12. The method according to claim 6, wherein at least one of the side flaps and the bottom flap of each blank are simultaneously coated with adhesive.

13. The method according to claim 6, wherein the flaps of each blank are coated with different adhesives.

14. The method according to claim 6, wherein one of the side flaps and the bottom ap are coated with latex and dextrin respectively.

References Cited UNITED STATES PATENTS 2,696,255 12/1954 Heywood.

2,920,539 1/ 1960 Doetsch 93-63 BERNARD STICKNEY, Primary Examiner.

Claims

1. A METHOD OF PRODUCING SINGLE PIECE ENVELOPES IN CONTINUOUS OPERATION, SAID METHOD COMPRISING THE STEPS OF FEEDING A CONTINUOU WEB OF UNIFORM WIDTH ALONG A PREDETERMINED PATH AND AT A PREDETERMINED SPEED, MAKING UNIFORMLY SPACE CROSSWISE CUTS THROUGH SAID MOVING WEB, EACH OF THE CUT-OFF WEB PIECES CONSTITUTING A PRELIMNARY ENVELOPE BLANK, ACCELERATING EACH OF SAID BLANKS TO A HIGHER PREDETERMINED SPEED CAUSING A LENGTHWISE SPACING OF SAID BLANKS ALONG SAID PATH, CUTTING OFF MARGINAL PORTIONS OF EACH OF MOVING BLANK TO DEFINE SIDE, BOTTOM AND CLOSURE FLAPS, FORMING PRELIMINARY FOLD LINES ALONG THE BASE LINES AT WHICH SAID FLAPS ARE JOINED TO THE MAIN BODY OF THE BLANKS, APPLYING ADHESIVE AT LEAST TO ONE OF THE SIDE FLAPS AND TO THE BOTTOM FLAP ON ONE SIDE THEREOF, AND FOLDING THE SIDE FLAPS AND THE BOTTOM FLAPS UPON ONE ANOTHER ALONG SAID FOLD LINES.