A METHOD AND AN ARRANGEMENT FOR PACKAGING TWO OR MORE PLASTER BOARDS

Abstract: A method and an arrangement for packaging two or more plaster boards by covering the transversal edge surfaces (4, 5), either partially or fully, of two or more sheets (1, 2) of plaster board with a tape (6), which has a width greater than the combined thickness of the edge surfaces, such that part (6a) of the tape will cover said edge surfaces (4, 5) and further parts (6b, 6c) of the tape can be fastened to outer board surface regions, that extend adjacent said edge surfaces (4, 5). This is effected by: a) selecting a given length to the tape (6); b) positioning the tape (6) adjacent the edge surface (4, 5) to be covered, such that an imaginary centre line (45) on the tape is located adjacent an imaginary centre line of the edge surfaces; c) bringing the tape (6) and the edge surfaces (4, 5) into co-action with one another, so that one part (6a) of the tape will cover the edge surfaces while further tape parts (6b, 6c) are folded for co-action with a respective one of the further board surface regions; (12, 13); and d) subjecting the tape to two simultaneous and uniform tape folding movements along the whole of its longitudinal extension, such as to fold the whole of the tape length along two mutually parallel fold lines (35, 36).

Description: TITLE of INVENTION: A Method and an Arrangement for Packaging Two or More Plaster Boards TECHNICAL FIELD The present invention relates primarily to a method for packaging plaster boards by covering two or more edge surfaces from two or more plaster boards with a tape, either fully or partically. The invention obtains particular application in packaging two or more plaster boards by covering adjacent transversal edge surfaces of said plaster boards with a tape, whose width exceeds the full thickness of the boards to be packaged, such as to enable one part or fraction of the tape to cover the boards edge surfaces and further enable two parts of the tape to cover and adhere to each of the board surface regions, which extends along said board edge surface and which are located adjacent thereto. The invention also relates to an arrangement of an apparatus, intended for carrying out the inventive method, comprising means for covering, either fully or partially, two or more edge surfaces of two or more sheets of plaster board with a tape, preferably a paper tape, having a width which exceeds the full thickness of the board composite intended for packaging, such that a first centered surface part or fraction of the tape covers the edge surfaces of said board composite, and that two further tape surface parts or fractions can be fastened on to a outer respective board surface region located adjacent a respective edge surface of one of said boards. BACKGROUND PRIOR ART It is known in the manufacture of plaster board to trans¬ versely cut the produced board into sheets of a given length and to package the sheets, two-by-two, with the front or fine sides of the sheets facing one another, in order to protect said sides from damage during handling and transportation. The sheets, placed front-to-front, are normally packaged with the aid of a tape having a width which exceeds the total thickness of the superimposed surface edges of the boards, so that the tape will also cover outer surface regions located adjacent said edge surfaces. The tape is coated with an adhesive on one side thereof, in order to adhere to said outer surface regions. According to one known method of applying tape to the edge surfaces of two sheets of plaster board, the tape is unwound from a tape storage reel as the edge surfaces of the boards to be packaged pass thereby. The tape is precoated on one side thereof with a latent adhesive layer, which is normally moistened and is centered in relation to said edge surfaces and then folded over outer board surface regions extending adjacent said transverse board edge surfaces, with the aid of known folding devices, whereafter the tape is cut adjacent the defining surface of the boards, or at the start and finish of said edge surface. When applying this known method it is necessary to move an pre-adhesive-coated, moistened paper tape in a slightly curved path, towards the edge surfaces of the boards to be packaged, and then to fold the tape in a direction perpen¬ dicular to said path, over two outer board surface regions extending along and adjacent to said board edge surfaces, which implies an undesirable double-fold of the tape in mutually different directions. It has been found in practice that a moist paper tape tends to pleat or snarl-up when being applied to the edge surfaces of the board, and it is difficult to cut the tape when it is moistened and folded. In order to more completely describe the prior art it should be mentioned that it is previously known a plaster board where the body is inclosed by covering sheets made from paper material and where one or both side edges are inclosed by a binder or a strip, which covers the edge of the board and is folded inwardly to overlie the two opposite sides of the faces of the board. Said strip is preferably scored before folding so as to give a straight or regular edge. Such a plaster board is shown and described in the U.S. Patent Specification No. 1. 395.032. It is also known from the U.S. Patent Specification No. 1.747.339 a wall board having a plaster core and paper faces and the longitudinal edges of this board are provided with reinforced means as channel strips, the edges of which overlap the edges of the wall boards. It is here suggested that the reinforced means can be formed from a flat strip and attached to the marginal edge of the board by bending or rolling operations and suitable secured against accidental removal from the board. Finally it is known from the U.S. Patent Specification No. 1.764.123 a method and means of applying edge covering strips to plaster boards. It should be noted that the prior arts disclosed in the above mentioned U.S. Patent Specifications are directed to the production of a single plaster board only and not to the package of two or more such plaster boards. SUMMARY OF THE INVENTION A study of the prior art as described above will show that a technical problem resides in the provision of conditions whereby the tape can be applied readily to the transverse edge surfaces of two or more boards in desired final tape length, for the purpose of packaging said boards, without encroaching on the conditions required for continuous board manufacturing processes. A further technical problem in this regard is one of enabling the full width of the tape to be folded around the edge surfaces of the boards along two mutually parallel fold lines, by subjecting the tape to a simultaneous and uniform folding movement along the whole of its longitudinal exten¬ sion. Another technical problem resides in the provision of conditions which will enable the tape to be advanced, while dry, to a position adjacent the edge surfaces to be covered, and to be cut in this position to a given length, and the cutted length to be coated with an adhesive layer in readi¬ ness for folding said tape about said edge surfaces. It will be seen that an associated technical problem is one of ensuring that the tape can be advanced readily without risk of adhesive or tape fastening to elements or components of the tape advancing device. Another technical problem is one of providing conditions, with the aid of simple means, which will ensure that ad¬ hesive-coated, tape of given length will not fasten to apparatus components, e.g. tape advancing devices, in the event of an interuption in the board manufacturing pro¬ cess. It will also be seen from the study of the prior art that a further technical problem resides in the provision of conditions, with the aid of simple means, whereby tape free from adhesive can be positioned so that an imaginary centre line on the tape is registered in relation to a corresponding imaginary centre line on the edge surfaces to be covered, such as to enable the tape to be then coated with adhesive while in said registered position, in preparation for application to the board edge surfaces immediately upon the edge surfaces taking a position which corresponds to said registered position. Similarly, a technical problem resides in the ability to orient a prepared length of tape in a registered position and to activate the tape adhesive, e.g. by moistening the adhesive, so that the tape is ready for use when the board is located in a position corresponding to said registered position. Another technical problem is one of extending considerably the length of time during which the adhesive-coated tape is pressed against the board surfaces, without encroaching upon the rate of board manufacture. It will also be seen that a technical problem resides in the provision of conditions, with the aid of simple means, whereby a cut length of tape can be transferred from a tape- length holder to one or two mutually parallel suction boxes which are operative in positioning the tape length correctly in relation to the edge surfaces to be covered, and which assist in fastening the tape to the aforesaid surface regions of respective board. Another technical problem is one of providing conditions, with the aid of simple means, whereby the suction boxes or other suitable means are able to urge the tape against said board surface regions so as to establish a strong adhesive bond between the tape and board. SOLUTION For the purpose of solving one or more of the aforesaid technical problems there is proposed, in accordance with the invention, a method for packaging two or more sheets of plaster boards, which has been transversely cut to size, by covering the transversely cut edge surfaces, either partially or fully of two or more, preferably two, sheets of plaster board with a tape in a manner to join said edge surfaces together, such that a first part or fraction of the tape covers said edge surfaces and further parts of the tape can be fastened on to outer board surface regions that extend adjacent said edge surfaces. The method being characterized by; a) selecting a given length to the tape; b) positioning the tape adjacent the transverse edge surface to be covered, such that an imaginary centre line on the tape is located adjacent an imaginary centre line of the edge surfaces; c) bringing the tape and the edge surfaces into abutment with one another, so that one part of the tape covers the edge surfaces while further tape parts are folded for abutment with a respective one of said further board surface regions; and d) subjecting said tape to two simultaneous and uniform tape folding movements along the whole of its longitudinal extension, such as to fold the whole of said tape length along two mutually parallel fold lines. According to one preferred embodiment of the invention, the tape is drawn from a magazine, for example a storage reel, and passed to a holding device, where it is cut into a pre¬ determined length with the tape dry. The tape is preferably passed from the holding device, via a subpressure, to one suction device or to two mutually parallel suction boxes located adjacent the tape. One surface of the tape is treated in a manner to exhibit adhesive properties, in a known manner. This can be effected in the apparatus described or, for example, by moistening tape that has been pre-treated to this end. In accordance with one embodiment of the invention, the tape and the board edge surfaces are moved into abutment with one another, by passing suction boxes,brushes or other suitable means over the aforesaid surface regions of the board with the tape held by said means and being permitted to slide there along. In this regard, the means is arranged to draw and press the tape towards and transversely of said surface regions. In accordance with one advantageous embodiment of the invention, a tear band or tear wire is passed through the apparatus together with the tape, substantially centrally thereof. The invention also relates to an arrangement for packaging two or more plaster boards by covering, either fully or partially, two or more edge surfaces of two or more sheets of plaster boards, normally two sheets, with a tape, preferably paper tape, having a width which exceeds the full thickness of said edge surfaces to be covered, such that a first, centered part of the tape will cover, and optionally adhere to, said board edge surfaces and further parts of the tape are able to adhere to respective outer surface regions of the board extending along said edge surface adjacent thereto, and adapting the arrangement in a manner to carry out a method significant of the present invention. In accordance with the invention, the length of tape is pre¬ selected, preferably to a length which is equal to or exceeds to a well defined extent the length of the transverse edge surface to be covered. First means are provided for position¬ ing the tape adjacent the edge surface to be covered in a manner such that an imaginary centre line on the tape is adjacent to and parallel with an imaginary centre line on the edge surfaces to be covered. Second means are provided for displacing the tape and/or the edge-surfaces towards one another for co-action with each other, such that the first centered part of the tape fully covers, or almost fully covers said edge surfaces. The aforementioned second means is arranged to further displace the tape and/or the edge surfaces in a manner such that the two further tape parts are simultaneously folded, by third means, into abutment with respective board surface regions, said second and third means co-acting to fold the tape along two mutually parallel fold lines, so as to effect a simultaneous and uniform folding motion along the whole of the longitudinal extension of the tape. In accordance with a further embodiment of the invention, the arrangement includes a tape magazine, e.g. a tape storage reel, from which the tape can be drawn and passed, while dry to a tape holding device. In accordance with one advantageous embodiment of the invention the arrangement includes fourth means by means of which the tape is transferred from the holding device to one suction device or to two mutually parallel and mutually spaced suction boxes. The arrangement also conveniently includes fifth means for treating one surface of the tape in a manner to- impart adhesive properties thereto or to activate latent adhesive properties thereon. The tape and the edge surfaces to be covered are, via said third means, arranged to co-act with one another in a manner such that the suction boxes, brushes or other suitable means are pressed over said surface regions of the plaster board. The suction boxes or other means e.g. brushes are arranged. to press the tape against said outer board surface regions during displacement of said boxes. The tape preferably supports a centrally positioned tear band or tear wire, so as to enable two sheets of plaster board held together by said tape to be readily separated one from the other. ADVANTAGES The advantages primarily characteristic of a method and arrangement according to the present invention reside in the possibilities of applying tape along the edge surfaces of sheets of plaster board to be packaged together with the aid of said tape, in a single operation and in a stationary position without decreasing the production rate, and in the possibility of enabling the tape to be posi¬ tioned more precisely in both the longitudinal and trans¬ verse direction. A further advantage resides in improved adhesion between tape and board, as a result of a longer press period, and in a reduced risk of pleating or snarling of the tape. The primary characterizing features of a method according to the invention are set forth in the characterizing clause of the following claim 1 , while the primary characterizing features of an arrangement of apparatus according to the present invention are set forth in the characterizing clause of the following claim 8. BRIEF DESCRIPTION OF THE DRAWINGS A n embodiment of an arrangement at present preferred and particularly suited for carrying out a method significant of the invention will now be described in more detail with reference to the accompanying drawings in which; Figure 1 illustrates part of a prior art plaster board manufacturing process, in which two sheets of plaster board placed one upon the other are joined together by means of tape, Figure 2 illustrates in perspective the principle contruction of a device for advancing dry tape to a registered position, in accordance with the invention. Figure 3 illustrates in side view and in the section "A" to "E" the sequence of transferring a tape from a tape holding device to two suction boxes, the application of an adhesive layer to one surface of the severed tape length, or acti¬ vation of an adhesive layer previously applied thereto; and a position in which the suction boxes apply the tape around the edge surfaces of two sheets of plaster board placed one upon the other. Figure 4 is a simplified view of certain components of apparatus operating in accordance with the inventive method, and Figure 5 is a simplfied view of an alternative embodiment exhibiting the noval features of the present invention. DESCRIPTION OF AN EMBODIMENT AT PRESENT PREFERRED Plaster board is manufactured in continuous lengths by mixing together calcinated gypsum material, essentially hemihydrated or semihydrated sulphate of calcium, a filler and/or an additive material, and water. The amount of water used is adapted to provide a slurry having a consistency and flow- ability which will enable the slurry to be spread over a carrier surface. The slurry is spread conventionally onto a web which is passed through rolls so as to impart a given thickness to the board, after which the board is passed through a given length of travel in order to enable the requisite chemical reactions to take place. In accordance with other known processes, the slurry is first spread between two lengths of paper board or card-board prior to being dried in a drying plant herefor, these lengths ultimately forming the front and rear faces of the finished composite board. Since these plant sections are known per se and do not constitute any part of the present invention, they will not be described in detail here. For the sake of completeness, however, Figure 1 shows in plan view two sheets of plaster-board 1 and 2 in fully overlapping relationship and located downstream of the drying section, with the rear side of one board 1 being clearly shown and the other board 2 being covered by board 1 and therefore not visible in the Figure. The rear sides of the board face away from one another, whereas the front or fine sides face toward one another. The thickness of the board is determined in the filling process, by the apparatus and paper board used. When the gypsum has hardened to a consistency at which it can be safely cut, subsequent to passing through a given reaction path, the plaster board is cut into lengths, slightly over size, and stacked in batches to be dried. The board lengths, hereinafter referred to as sheets, are then placed in pairs, two-and-two, with the front or fine sur¬ faces of each pair facing towards one another. The plaster board sheets 1 and 2 are then cut to a given length in a cutter 3, thereby to form a transverse edge surface 4 on the one sheet 1 and a corresponding transverse edge surface 5 on the underlying sheet 2. It will be understood that the oppositely located edge surfaces (not visible) are also cut. It is assumed in this case that the width of the sheets has been clearly defined in the manufacturing process, thus obviating the need to cut along the long sides of the sheet. In this known process, each of the cut edges of respective sheets 1, 2 is coveredby tape ' 6,which is wound on a bobbin 7 and extends over a roll 8 and is passed therefrom through a device 9 operative either in applying an adhesive coating to one surface of the tape or in activating an adhesive coating previously applied to said surface. A further roll 10 urges the tape against the edge surfaces 4, 5, so that part of the tape will lie against said edge surfaces, while further rolls 11, 11 * located downstream of the roll 10, on respective sides of the plaster-board sheet, press further parts of the tape against board surface regions that extend along said edge surfaces adjacent thereto. For the sake of simplicity Figure 1 shows the application of tape 6 to solely the visible edge surface 4 of the sheet 1. For the same reason, the apparatus used herefor is shown in a highly simplified manner. That part of the tape 6 which is intended to cover the edge surfaces 4, 5 is referrenced 6a, whereas those parts of the tape which are intended to cover the board regions 12, 13 that extend adjacent said edge surfaces 4, 5 are referenced 6b and 6c respectively. The tape 6 extending between the mutually adjacent sheets 1 and 1 ' is severed by cutting means 14, so as to enable the sheets to be packed in pairs with severed tape. Figure 2 illustrates an arrangement of apparatus according to the invention for covering either fully or partially, the edge surfaces of two or more sheets of plaster board, normally two, with tape, preferably paper tape, the width of which exceeds the combined thickness of said mutually superimposed edge surfaces, such that a first centered tape part 6a will cover and optionally adhere to the edge surfaces 4, 5, and such that two further tape parts 6b, 6c will cover, but primarily adhere to sheet surface regions 12, 13 which extend adjacent the edge surface of respective sheets 1, 2. The inventive arrangement illustrated in Figure 2 includes a first bobbin or reel 20 having wound thereon a tear band or tear wire 21, and a second bobbin or reel 22 upon which the tape 6 is stored. The tape 6 and the tear band 21 are passed through a pair of feed rolls 23 and 24 and a guide 25 to a holding device 26, which comprises an upper U-shaped rail 27 and a lower U-shaped rail 28. The longitudinal extension of the rails is substantially equal to the length or width of the in¬ tended edge surface. The tape 6 is advanced through the guide 25, via the feed rolls 23, 24, into the holding device 26 until the edge surface 6a 1 of the tape 6 breaks a light beam 30 projected by a light-emitting source 31 onto a light-receiving de¬ vice 32, which is arranged to produce a signal when said light beam is broken. The signal produced by the light- receiving device 32 is delivered to known circuit means (not shown) which stop the rolls 23 and 24 in response to said signal. The tape 6 is then cut at the location referenced 14 in Figure 1 to a length which is equal to or which exceeds by a well defined extent the length of the intended edge surface 4 , 5 of the plaster board. Alternatively the tape can be cut to a length which is equal to or slightly less than the length of the plaster- b oard. It is preferred, however, to cut the tape to a length which is some centimetres longer than the length of the edge surface to be covered and for the excess length to project beyond said edge surface. The principles of the invention will be better understood from Figure 3, which illustrates a sequence significant of the invention in sections "A" to "E". As previously mentioned, the tape 6 is preferably cut to a length which is equal to or slightly longer than the length of the intended edge surface 4, 5. The cut tape length 6 is positioned adjacent the edge sur¬ face of the board by first means in the form of the holder 26, operative in positioning an imaginary centre line of the tape 6 adjacent to and parallel with an imaginary cen¬ tre line 45 on the edge surfaces of the board. The tape is displaced into abutment with the edge surfaces by second means, these means not being illustrated in the accompanying drawings since they are known per se, although the technical effect of this displacement is illustrated in section E of Figure 3. When the tape is displaced in the aforesaid manner, the first centred part 6a of the tape is able to cover the edge surfaces 4, 5. The aforesaid second means is also operative in further displacing the tape and/or the edge surfaces in a manner such as to enable the two further parts 6b, 6c of the tape to be folded into abutment with a respective surface region 12, 13 of the board by means of third means, in the form of suction boxes, said second and third means co-acting with one another in a manner to fold the tape simultaneously along two mutually parallel fold lines 35, 36, so as to effect a simultaneous and uniform folding movement along the full longitudinal extension of the tape length 6. The sequence of events significant of the invention can be said to commence, with reference to section A of Figure 3, from the point at which the tape 6 is located between and carried by the rails 27, 28. In practice, the configuration of the rails 27 and 28 conforms more favourably to the thickness of the tape 6, and the rails 27, 28 will preferably be positioned closer to the suction boxes 37, 38. The size of the channel in the rails 27 and 28 is such as to accommodate almost the full thickness of the tape 6, this channel preferably having a width which is smaller than 1 mm. Although not shown in detail, the illustrated arrangement includes fourth means which when the cut tape length 6 is located between the rails 27 and 28 lifts the rail 27 up, as shown in section B of Figure 3, therewith causing a sub-pressure to be applied to the suction box 37, such as to bring the tape part 6b into co-action with the suction box 27 via a hole 37a or a line of holes 37a. As illustrated in section C of Figure 3, the rail 28 is then displaced, via said fourth means, away from the tape 6 and a subpressure is similarly applied to the suction box 38 so that the tape part 6b is brought into co-action with the suction box 38 via a hole 38a or a line of such holes. As illustrated in section D of Figure 3, when the tape 6 is in co-action with the suction boxes 37 and 38 the one surface 6' of the tape 6 is treated, via fifth means (not shown) in a manner to exhibit adhesive properties subse¬ quent to said treatment. In this regard it is conceivable to provide a roll 40 of adhesive-coated material, which is rolled out onto the tape 6, or that the surface 6 ' of the tape 6 is pre-treated with a substance which becomes adhesive upon contact with water, or the tape surface 6 1 can be coated with water or adhesive material through nozzles (not shown) . As illustrated in section E of Figure 3, the cut tape length 6 * and the edge surfaces 4, 5 are arranged to co-act with one another via said third means, to an extent such that the suction boxes 37, 38 pass over the said surface regions of the sheets of plaster board 1 , 2. It is also proposed that the suction boxes 37, 38 are ar¬ ranged to press the tape 6 against said board surface regions 12, 13 during said displacement, such as to gener¬ ate greater frictional forces than those generated solely by the suction forces between the tape parts 6b and 6c and the suction boxes, so as to stretch the tape 6 uniformly over the edge surfaces of the board. In the embodiment illustrated in Figure 4, the first means has the form of a motor 41 which drives a spindle 42 for raising and lowering the rail 27, and a motor 43 which drives a spindle 44 for raising and lowering the rail 28, such as to register the centre line of the cut tape length 6 with the centre line 45 of the sheets of plaster-board 1, 2. Figure 4 also illustrates schematically second means 46 operative in enabling the tape 6 and the edge surfaces 4, 5 to be displaced towards and away from one another, into and out of co-action with one another, so that a first centered tape part 6a covers and optionally adheres to the edge surfaces 4, 5, this being effected by displacing the suction boxes 37, 38 towards the plaster-boards 1 and 2. Said means is also used to effect the return movement. The third means comprises the suction boxes 37, 38, which have been given a suitable curvature 37b and 38b. The illustrated arrangement of apparatus enables the two further tape parts 6b, 6c to be folded into abutment with a respective board surface region 12, 13, said second and third means co-acting to fold the tape simultaneously along two mutually parallel fold lines in the aforedescribed manner. The suction box 37 can be raised and lowered by means of the device 15 illustrated schematically in Figure 4, there¬ by -to enable the distance between the mutually opposing surfaces of the suction boxes 37 and 38 to be adjusted to the prevailing thickness of two superimposed sheets of plaster-board. Although not ' shown in Figure 4, a similar device is pro¬ vided for this and other adjustment purposes, so as to enable the rail 27 with associated motor 41 and/or the rail 28 with associated motor 43 to be raised and lowered in a similar manner. In the Figure 4 embodiment, the roll 40 is sprayed with water from a valve 41 , and can be moved up and down along the tape 6 with said tape held firmly by the suction boxes 37 and 38, by means of a pneumatic piston-cylinder device 52, It should be note that Figures 3 and 4 illustrate the ar¬ rangement in side view. The length of the suction boxes 37 and 38 should conform to the length of the rails 27 and 28, which means that the illustrated holes 37a and 38a in reality consist of one or more rows of suction orifices extending along the whole suction box. It will be under¬ stood that each suction box may be divided into sections, so that the subpressure, through a row of holes 37a, will act, e.g., from the centre of the suction boxes towards the end parts thereof, thereby to have a stretching effect on the cut tape length 6. Naturally, this may also apply to the suction box 38. The tape 6 may be cut to a length at which, when applied to the edge surfaces 4, 5, part of the tape will extend beyond the defining surfaces of said edge surfaces by from 2-5 cm, so as to provide a grip for the tear wire or tear band when wishing to separate the mutually joined plaster-board sheets. Although the suction boxes are positioned parallel with the edge surfaces in the illustrated embodiment, and are there¬ with intended to be displaced over the sheets of plaster board while retaining their position, it also lies within the scope of the invention to incline the suction boxes slightly, so that the tape is applied progressively onto the edge surfaces to be covered. With reference to the alternative embodiment shown in Figure 5 it is here shown one suction box 55, which is arranged adjacent the tape 6 and intended to be moved to the right and under pressure hold the tape 6 in registered position. A further movement towards right and the tape 6 is in co- action with the transverse edges of the two plater boards 1 and 2. In this position two brushes 56 and 57 are moved still more to the right and said movement is turning and pressing the upper and lower further parts of the tape 6 onto outer upper and lower board surface regions 12 and 13. Then the brushes 56 and 57 and the suction box 55 is returned to its resting position shown in Figure 5. It should be understood that many of the means illustrated in Figure 4 also are necessary for the proper function of the embodiment shown in Figure 5 but these have been omitted for simplicity reasons. It will be understood that the invention is not restricted to the exemplifying embodiment described in the aforegoing and illustrated in the accompanying drawings, and that modifica¬ tions can be made within the scope of the following claims.

Claims: CLAIMS 1. A method for packaging two or more plaster boards by covering the edge surfaces, either partially or fully, of two or more sheets of plaster board with a tape, which has a width greater than the combined thickness of the edge surfaces, such that one part of said tape will cover said edge surfaces and further parts of the tape can be fastened to board surface regions, that extend adjacent said edge surfaces, characterized by the sequence of; a) selecting a given length to the tape; b) positioning the tape adjacent the edge surface to be covered, such that a centre line on the tape is located adjacent a centre line of the edge surfaces; c) bringing the tape and the edge surfaces into co-action with one another, so that one part of the tape will cover the edge surfaces while further tape parts are folded for co- action with a respectivev one of said further board surface regions; and d) subjecting said tape to two simultaneous and uniform tape folding movements along the whole of its longitudinal extension, such as to fold the whole of said tape length along two mutually parallel fold lines. 2. A method according to Claim 1, characterized by drawing the tape from a magazine reel, and passing the tape to a holding device, and there cutting said tape to a pre-deter- mined length. 3. A method according to Claim 2, characterized by passing the tape from the holding device, via a subpressure, to one suction device or to two mutually parallel suction boxes. 4. A method according to Claim 1, 2 or 3, characterized by treating one surface of the tape in a manner to exhibit adhesive properties either by applying adhesives or by activating latent adhesive properties. 5. A method according to any of the preceding claims, characterized in that the tape and the board edge surfaces are moved into co-action with one another, by passing suction boxes, brushes or other suitable means over the aforesaid surface regions of the plaster board. 6. A method according to Claim 5, characterized by pressing the tape against said surface regions by means of suction boxes, brushes or other suitable means. 7. A method according to any of the preceding claims, characterized by passing a tear band or tear wire through the apparatus together with the tape, substantially centrally thereof. 8. An arrangement for packaging two or more plaster boards by covering, either fully or partially, two or more edge surfaces of two or more sheets of plaster board, normally two sheets, with a tape, preferably paper-tape, having a width which exceeds the full thickness of said edge surfaces to be covered, such that a first centered part of the tape will cover said board edge surfaces and further parts of the tape are able to adhere to respective surface regions of the boards extending along said edge surface and adjacent thereto and adapting the arrangement in a manner to carry out the method according to one or more of the preceding claims, characterized in that a long length of said tape is cut to a length, preferably equal to or exceeding the length of the edge surface to be covered; in that first means are provided for positioning the tape adjacent the edge surfaces to be covered in a manner such that an imaginary centre line on the tape is adjacent to and parallel with an imaginary centre line on the edge surfaces to be covered; in that second means are provided for displacing the tape and/or the edge-surfaces towards one another for co-action with each other, such that the first centered part of the tape fully covers, or almost fully covers said edge surfaces; in that said second means is arranged to further displace the tape and/or the edge surfaces in a manner such that the two further tape parts are simultaneously folded, by third means, into abutment with respective outer board surface regions, said second and third means co-acting to fold the tape along two mutually parallel fold lines, so as to effect a simultaneous and uniform folding motion along the whole of. v the longitudinal extension of the tape. 9. An arrangement according to Claim 8, characterized in that the arrangement further includes a tape magazine from which the tape is drawn and introduced into a tape holding device. 10. An arrangement according to Claim 8 or 9, characterized in that the arrangement includes fourth means by means of which the tape can be transferred from the holding device to one suction device or two mutually parallel and mutually spaced suction boxes. 11. An arrangement according to Claim 8, characterized by fifth means for treating one surface of the tape in a manner to impart adhesive properties thereto or activate latent adhesive properties thereon. 12. An arrangement according to Claims 8-11, characterized in that the tape and the edge surfaces to be covered are, via said third means, arranged to co-act with one another in a manner such that suction boxes, brushes or other suitable means are pressed over said surface regions of the plaster board.

Inventors: CARLSSON MATS, CARLSSON, MATS
Applicants: FLAEKT AB
Application year: 1987
Main classification: E04C2
IPC codes: B28B11, E04C2