Mail Parcel sealing method and apparatus

Abstract: Printed material (P) in form of single sheets (20) or groups of sheets is converted into a sealed parcel ready for mailing by glueing along all the perimetral edges (I,II,III,IV) of the cover or parcel of sheets, in which a folding operation has been possibly previously carried out in order to take the sizes of a normal envelope for mailing.

Description: The present invention relates to the sealing of covers consisting of a number of paper sheets, particularly in preparation for the mailing. In the following description specific reference shall be made to mail shipping parcels, it being meant that it should not be construed in limiting sense about the scope of the present invention, since the sealed covers obtained by the method and apparatus of the present invention may be provided for different uses. It is known that, besides the normal mailing system in which the printed material in form of sheets to be mailed is enclosed into an envelope which in turn is sealed either totally or partially at the open side for the introduction of the aforesaid printed material, in recent years different systems have been proposed and adopted expecially in connection with the exceedingly wide and capillary diffusion of the so-called continuos forms and of the fast printing, for example in laser printing centers. In this case, as a matter of fact, the form is also called as self-enveloping sheet and has parts which are previously glued; upon the printing is completed a folding is carried out according to predetermined folding lines and the sealing takes place preferably by activating the glue, for example by application of heat which causes the previously applied glue to be reactivated. In this second case, obviously, it is necessary to have suitably punched and pre-glued sheets or forms, which are useful only for specific uses: typical examples are the payment forms issued from public or private companies supplying services such as phone services, electric supply, potable water, etc. In these cases the requirement imposed by the public mail service, namely the accessibility to the content of the covers for the possible postal inspection (as a matter of fact these are normally mailings carried out at speciall tarif) makes it unavoidable, not only to shape the punched sheet so as to fulfill this requisite, but also use the so-called reversible glues, permitting the opening and the closing again of the cover. However there are several cases in which a certain number of sheets constitutes the material to be transmitted to the addressee. In this case the only solution is still that of the conventional envelope of the above mentioned type. A typical example is that of the transmission of the bank statements of account, which for most cases and customers, consist of a certain number of subsequent sheets. Another example consists of the transmission, by the aforesaid service supplying companies, of the documents supporting the figures debited by the payment bills. This problem is particularly serious when the documents to be transmitted (for example in the typical case of the bank statements of account) are processed and printed at a very high operation rate, which in the above cited example uses computerized electrical accounting centers and laser printers operating at high speed (of the order of 80 cm/sec.); the folding along predetermined folding lines is also carried out mechanically and is made automatic: however the introduction into the envelopes causes the whole operation to be slowed down in an untolerable measure, sometimes making it almost superfluous the recourse to more and more sophisticated and fast apparatus. By the way and moreover the separated envelopes cause greater expenses not only owing to their intrinsic cost, but also owing to the greater weight thereby given to the covers to be mailed and which is reflected in the mailing costs which as a matter of practice and almost universally are univocally dependent on the weight of the letter to be mailed. Main purpose of the present invention is that of providing a solution of the aforesaid problem, which is industrially feasible and economically advantageous. A most specific purpose of the present invention is that of providing a method and an apparatus permitting the shipping of sealed covers without use of a separate envelope. These and other purposes are attained by the present invention through a method and an apparatus for the sealing of covers, particularly ready for the mail shipping. Thus the method according to the present invention according to a first embodiment thereof is characterized in that the cover to be sealed for the mailing, consisting of a plurality of rectangular sheets, two of which form the outer parts of the cover, each sheet having four edges and a predetermined size, and the sheets being in alignment along all edges, comprises the step of back glueing all four edges of the sheets so that all sheets are sealed together without having glue interfering with the inner faces of said outer parts. According to another embodiment of the method of the invention wherein the cover to be sealed consists of at least one substantially rectangular sheet comprises the steps of a) folding the at least one sheet along at least one line to divide the at least one sheet into a plurality of regions, whereby two of the regions form two outer parts of the cover such that the outer parts have a predetermined size and all four edges in alignment with each other, and b) back glueing all four edges of the outer parts so that all regions are sealed together without having glue interfering with the inner faces of said outer parts. According to a third embodiment of the invention the method for sealing covers consisting of a plurality of rectangular sheets, two of which form the outer parts of the cover, each sheet having four edges and a predetermined size, comprises the steps of back glueing all four edges of each sheet and then reactivating the back glued edges of the sheet with all their edges in alignment so that all sheets are sealed together. In turn the apparatus according to the present invention for sealing covers according to the first and second method of the invention comprises conveying means for conveying the sheets or at least one folded sheet to be sealed together, a plurality of back glueing stations for back glueing each edge of the sheets or of at least one folded sheet with their edges being in alignment and guiding means for presenting each edge of the sheets or at least one folded sheet to the related back glueing station. According to a preferred embodiment of the apparatus of the present invention, in which the glue is applied in situ to the four sides of the covers to be sealed, said carrying means consist of a plurality of rollers supported by a frame, retaining means at each back glueing station temporarily retaining the cover during the back glueing. The glue, in turn, is applied by means of conical roller heads, drawing it from a corresponding basin containing the glue in liquid form suitable for the application whereas downstream of each applying station there are preferably foreseen fan means for the drying of the immediately upstream applied glue. Alternatively, the application of the glue at each side in the corresponding station is carried out by means of glue applying nozzles, the glue being sufficiently liquid, said nozzles being fed by corresponding supplying means for the dosed supplying of glue in the afore mentioned conditions. As it will be appreciated from the following detailed description, the method and apparatus of the invention are based on a technique which to date has been only tested and used in the book binding field, namely to obtain a firm joint between a number of superimposed and matching sheets by coating with glue only the paper of the sheet parcel. As it is well known, in this manner the sheets are kept firmly together without having the glue interfering with the surface or the faces of the single sheet. When the sheets are to be separated from each other it is enough to apply a separation or tearing action which takes place only at the edges glued to each other, (as it occurs for example in the case of the so-called note books). The peculiar features and advantages of the present invention shall appear more clearly from the following detailed description, made with respect to the enclosed drawings, in which: figure 1 is a perspective schematic view of the apparatus according to the present invention in a first embodiment; figure 2 is a plan view, also necessarily schematic, of the apparatus of figure 1; figures 3,4,5 and 6 are views like figure 1 showing the four operating phases for the sealing of a cover of sheets. figures 7 and 8 are views like figures 1 and 2 respectively, showing another embodiment of the apparatus according to the invention; figures 9 to 15 show the different sealing operating phases referred to a paper sheet; figures 16 and 17 illustrate, in side view and in a partially enlarged detail view, respectively, the case of a number of sheets to be sealed in form of cover for the mailing, and figures 18, 19 show a particular modified embodiment of the method according to the present invention. For sake of clear disclosure there will be firstly commented what is shown in the figures 9 to 15, in connection with the method of the present invention. The figure 9 shows a paper sheet, for example a letter paper sheet, indicated by the reference 20 and thus having one face 20A and one face 20B. On this sheet there are indicated by dashed lines 22 and 24 two folding lines corresponding to the common lines along which a sheet of letter paper is folded before the introduction into a normal rectangular envelope for the mailing. In the figures 10 and 11 two different manners are represented according to which the sheet 20 may be folded along the lines 22 and 24; the arrows F in the two figures represent the pressing direction of the folded sheet so as to bring it into the configuration corresponding to that which it is contained in an envelope consistent with the standard size for mailing. In the case represented in figure 10 the sheet 20 is Z folded whereby for carrying out the method of the present invention the written communication to be transmitted to the addressee must be contained in the two areas 21 and 23 of the three areas (the third one being the area 25), in which these lines divide, even only ideally, the height or the greatest dimension of the sheet 20. In the area 25 it will be thus written the address of the addressee and if desired that of the sender (as sometimes it is made by placing the address of the sender in the high left part of the normal envelopes). In the case of fig. 11, on the contrary, the whole height of the face 20A is useful for the aforesaid written communication, whereas the address of the addressee (and possibly of the sender according to the already mentioned mode) must be written or printed on the face 20B at the areas 21 or 23. When the movement indicated by the arrows F is completed up to have the folded sheet completely flattened, it is in both cases in the condition illustrated in figure. 12 and sidewise in the condition of the figures 13 and 14 in the case of fig. 10, whereas the side view in the case of fig. 11, is that shown for sake of simplicity only by fig. 15. From fig. 12 it is clearly seen that the sealing by glueing must involve the four sides I, II, III and IV. The present invention thus contemplates that the sheet 20, folded to the final condition of fig. 12, is glued along the four above said sides, thus defining a sealed envelope ready and suitable for mailing. Of course in the case of a number of sheets to be sent together, which constitutes also the case that up to date has not found a different solution apart from the use of the conventional envelope, the phases are similar except that two possibilities exist, namely that consisting in folding each sheet in the illustrated manner, and then superimposing the sheets in flattened condition carrying then out the said glueing. The other possibility, which is advisable especially when the sheets to be sent together are really 3 or 4, is that of having the spread sheets matching and to proceed firstly to the folding and then to the sealing of assembly of folded sheets. Thus, in the case of figures 14 and 15 the cover P consists of only two folded sheets, whereas in the case of the figures 16 and 17 the sheets forming the cover are three and are shown in the folded and sealed condition; in that case the reference 28 indicates the glue thread or frame by which all the sheets are kept sealed together. Coming now to figures 1 and 2 a first embodiment is shown of the apparatus according to the present invention comprising a frame 30, shown in schematic and essential form, whereby it is meant that the same, as well as the other mechanical components which will be described hereinafter, can be completed from the structural and mechanical point of view at the time of manufacturing thereof. Onto the two upper surfaces the frame 30 a plane of translation is individuated for the covers to be sealed, this plane comprising a number of rollers or cylinders 32 idly mounted at their two ends; of these cylinders those indicated by the reference 32A, that are placed at the four sealing stations indicated by the references IA, IIA, IIIA e IVA, have longitudinal axes inclined with respect to the horizontal plane so as to promote the displacement of the cover being processed towards the glue applying device provided in each station. For the controlled rotation of the rollers or cylinders 32 and 32A around their axes there is provided at least one belt 34 having it operating or upper reach passing alternatively above and under the rollers or cylinders 32 and 32A which are thus rotated by friction. The belt 34 forms a closed ring thanks to a transmission pulley 36 and to a driving or operating pulley 38 mounted at the end of the motor shaft of a motor 40, for example of the stepped type, which causes the pulley 38 and consequently, through the belt 34, the rollers 32 and 32A to be rotated intermittently. By the way, instead of the belt 34, equivalent motion transmission means can be used such as for example a chain and pinion transmission mounted at the head end or at one end of the rollers or cylinders 32 and 32A, possibly externally with respect to the cover transfer plane. In fig. 1 it is observed that as a matter of fact the apparatus comprises two horizontal transfer planes for the covers to be sealed, ortogonally positioned to each other and each of which serves two sealing stations, whereby also the driving in rotation of the idle rollers or cylinders 32 and 32A takes places by means of two separated belts 34 (one for each plane), having the respective motor 40 and pulleys 36 and 38. At each sealing station a glue applying device is provided comprising a conical head 42 mounted to an axis 44 driven into rotation by controlled motor means (shown in fig. 2) comprising a motor 48 serving the two different conical heads 42 of two subsequent stations, namely IA and IIA as well as IIIA and IVA, through a transmission comprising the two pinions 50, 52, the transmission shaft 54 and the line transmission group 56. Each conical head 42 is mounted so that, during the rotation, it is periodically dipped into a basin 46 containing the desired glue in the liquid state or with a controlled fluidity; it is for example obtained in a known manner by having the basin 46 provided with suitable means for the controlled heating and termal regulation thereof. The axis 44 of each conical head is mounted with a certain inclination with respect to the advancing direction of the covers, namely with respect to the line perpendicular to the adjacent transfer plane, so that the conical surface of the conical head 42 is practically almost tangent to the adjacent side of the frame. In figure 2 this arrangement is clearly shown mainly as regards the position of the glue applying conical heads. Each station is furthermore provided with quick drying means, represented for example by the fans 58. It is lastly to be observed that in the shown embodiment for the mounting of the rollers 32A in an inclined position there are alternatively foreseen supporting side plates 60 and relieved parts 62 formed onto the upper plane of the frame 30. The operation of this embodiment is shown in the succession of its phases in the figures 3 to 7, each showing the cover to be sealed at a specific station. It is evident that in the real operation each station shall be operating simultaneously to the others, whereby it is sufficient to adjust the advancing speed of the belts 34 and thus the rotation speed of the rollers or cylinders 32 and 32A so that each cover arrives at a station when the sealing in the same station of the desidered side of the immediately previous cover, which has already abandoned this station, has been completed. Starting from fig. 3, the folded cover of fig. 13, generically indicated with the reference P is brought with its side I into contact with the corresponding conical head 42 which upon rotating draws the glue from the basin and brings it upwardly until sufficient liquid glue is applied to the aforesaid side I of the cover P. Immediately downstream the same side I undergoes the blowing action of the fan 58 whereby during the next advancement drippings of glue from the said side are avoided. During the downstream advancement, thanks to the inclination of the cylinders 32A the cover P is brought with its side III into contact with the conical head of the second station IIA and the operation is identically repeated whereafter the cover P with the two opposite side I and III already sealed passes to the stations IIIA and IVA of the apparatus, at which the application of glue onto the two other opposite side II and IV takes places. The cover P then comes out of the apparatus in a perfectly sealed and dry condition, ready for the possible stamping and the other mailing operations. It is evident that the glue application operation takes adequately place independently from the thickness of the cover P thanks to the conical shape of the applying heads. It is moreover to be observed that in the above description specifical reference has been made to single basins of glue which, however can be joined, as in the representation of the figures 1-7, in only one basin extending below the plane defined by the frame 30, so that the conical heads can draw and apply glue under the same identical conditions of temperature and viscosity or fluidity. In the same figures it is moreover shown for each station by the reference 64 a temporary stopping member for the cover to which the glue is being applied, this member consisting of a rod or plate journalled at one end to the frame 30 and controlled in a known manner to be displaced from a raised (or upwardly rotated) position in which permits the cover to come close with the side to be glued to the corresponding conical head, to a lowered or stopping position, in which it prevents the cover from being displaced from the desired position during the contact with the conical head and viceversa. It is evident that the driving and control means for the displacement of the member 64 between the two indicated positions have not been represented, being conventional organs within the reach of the skilled artisan, upon their function has been individuated and clarified. Taking now into considerations the figures 7 and 8, there is shown another embodiment of the apparatus of the present invention; for sake of understanding elements which are identical or strictly similar to those of the figures 1 and 3 are indicated by the same reference numbed increased by 100. From the comparison between the figures 7 and 8 and the corresponding figures 1 and 2, it is readly appreciated the fact the the main difference resides in the manner and in the means for the application of the glue to the four sides of the cover P: as a matter of fact in the case of the figures 7 and 8 each station for the sealing by glueing is provided with a dispensing nozzle 66 connected, through a branch 68, to a duct or supplying header 70 serving all four dispensing nozzles of the four stations and is in turn connected through a connecting duct 72 to a gear feeding pump 74, actuated from an electrical motor 76 and which draws liquid or fluidized glue 80 from a preferably thermally controlled basin 78. The operation of the apparatus according to this embodiment is like that already described with respect to the embodiment of figures 1-8 whereby it is not necessary to repeat detailedly the description of the operation. Coming now to figures 18 and 19, they relate to a further operating solution of the method according to the present invention to which reference has been made in the preamble of the specification. As already mentioned, besides the direct application of the sealing glue in the processing phase of the paper sheet or sheets coming from the printing step, it is possible and foreseen by the present invention that the paper is pre-glued, namely provided with a seam of glue placed along the whole perimeter of each sheet; the glue, being previously applied and dried so as to permit the different operations to which the same sheet is subjected before sealing and the mailing, is reactivated for example by applying a dosed amount of heat or of thermal energy or of energy of another suitable type, whereby it is admixed with the glue of the edges of the other sheets which together that being in consideration concur to form the cover to be sent or with the glue of the other edges of the same sheet when the cover is formed by only one sheet. In this case, as it is shown in the cross section view of figure 19, the sheet 120 is combined with two protecting sheets, which can also be called cover sheets, 124 and 126, identical to the sheet 120 except that they are used as such, or to print thereonto only the address of addressee and the data of the sender. By the reference 128 there is indicated and shown on enlarged scale the sealing seam which is provided all around the cover formed from the three sheets 120, 124 and 126 and resulting from the melting and solidification of the seams 122 of which each sheet 120 is provided. It is also foreseen and foreseable that instead of three sheets they are reduced to only two sheets, in the sense that the sheet 120 is also acting as a cover sheet by its back face. Of course the sheets 120 can be greater as to their number and in that case the sealing seam 128 extends for the whole thickness of the resulting cover. When the latter is of very great thickness it is possible and foreseen by the present invention that the sealing seam 128 is reinforced by an additional member, for example a paper or tissue ribbon or another member having a similar function as it occur for example in the case of the book binding ribs for books. In the above description reference is constantly made to the glues and to the glueing there being obviously meant glues suitable for paper supports. Since this type of glue is well known in this art (it is enough to take it into consideration the glues already used in the normal envelopes, both of reversible and of non reversible type, or those presently used for the pre-glueing of the so called self-enveloping forms) the skilled artisan shall be enabled to easily make his choice without need of particular teaching. Even in the case of the figures 18, 19, the operations of sealing of glueing already described with respect to the previous embodiments are identically repeated, except that instead of the device for the application of liquid or fluid glue drawn from a thermally regulated device there will be used means for the activation of the glue forming the edge seam of each sheet, such as for example conical heads as those shown in the figure 1 and 2 or even cylindrical rollers suitably heated and thermally controlled; by the way in this case the glue must be of the type which can be activated by heat.

Claims: Method for sealing covers consisting of a plurality of rectangular sheets, two of which form the outer parts of the cover, each sheet having four edges and a predetermined size, and the sheets being in alignment along all edges, comprising the step of back glueing all four edges of the sheets so that all sheets are sealed together without having glue interfering with the inner faces of said outer parts. Method for sealing covers consisting of at least one substantially rectangular sheet comprising the steps of a) folding the at least one sheet along at least one line to divide the at least one sheet into a plurality of regions, whereby two of the regions form two outer parts of the cover such that the outer parts have a predetermined size and all four edges in alignment with each other, and b) back glueing all four edges of the outer parts so that all regions are sealed together without having glue interfering with the inner faces of said outer parts. Method for sealing covers consisting of a plurality of rectangular sheets, two of which form the outer parts of the cover, each sheet having four edges and a predetermined size, comprising the steps of back glueing all four edges of each sheet and then reactivating the back glued edges of the sheet with all their edges in alignment so that all sheets are sealed together. Method according to claim 1 - 3, characterized in that the predetermined size corresponds to the size of standard envelopes. Method according to claim 2, characterized in that the glueing is carried out after the folding. Apparatus for sealing covers according to one of claims 1,2,4,5 comprising conveying means for conveying the sheets or at least one folded sheet to be sealed together, a plurality of back glueing stations for back glueing each edge of the sheets or of at least one folded sheet with their edges being in alignment and guiding means for presenting each edge of the sheets or at least one folded sheet to the related back glueing station. Apparatus for sealing covers according to claim 6, characterised in that said conveying means consist of a plurality of rollers, said rollers being inclined towards one side of an apparatus frame at which a back glueing station is provided, the apparatus further comprising retaining means being provided at each back glueing station for temporarily retaining the cover during the back glueing. Apparatus for sealing covers according to claim 7, characterised in that the glue of the back glueing is applied by means of conical roller heads which are immersed in a corresponding basin containing said glue in a liquid or fluid state suitable for the application thereof. Apparatus for sealing covers according to claim 8, characterised in that fan means are provided downstream of each said conical head for drying the glue applied by said conical head. Apparatus for sealing covers according to claim 8, characterised in that the application of the glue at each side of the cover at the corresponding back glueing stations carried out by means of dispensing nozzles by which enough liquid glue is dispensed, feeding means being provided to fed said nozzles with correspondingly dosed liquid or fluid glue. Apparatus for sealing covers according to claim 7, characterised in that said retaining means consist of a rod or plate journalled at one end to the frame and controlled in a per se known manner for the displacement between a raised position and a lowered stopping position. Sheet of paper useful in the sealing of covers according to the method of claim 3, characterised by having all four edges backglued.

Inventors: MESCHI LUCIANO, MESCHI, LUCIANO
Applicants: MESCHI IND GRAFICA, INDUSTRIA GRAFICA MESCHI S.R.L.
Application year: 1992
Main classification: B43M5
IPC codes: B43M5