Abstract: A method for continuously manufacturing a thin wall tube of an extrudable material, preferably a polyolefine, having a wrapper of a metal foil.A thin wall extrudate is discharged from an extruder and a web of a metal foil having an adhesive layer thereon is fed against the outside of the tube and brought to fully cover the envelope surface of the tube with said layer facing the tube.Thereafter the tube is fed into an opening in a housing forming a pressure and temperature zone.The lamination pressure for laminating the metal foil to the tube is made selfadjusting by adapting the temperature and/or the efficient opening diameter of said opening to the inherent deformation resistance of the tube.

Abstract: A sealer for inflated balloons, consisting of a casing having a vertical transverse channel open at its upper end. A toothed wheel is mounted on one side of the channel and a resilient strip on the other side. The strip has an operative portion extending in the channel in curved abutting relation to the wheel. The latter and the strip cooperatively define a V-shape notch. Pressure adhesive tape extends from a spool around the toothed wheel. A cutting member is pivoted below the wheel and the strip. Pressing a balloon neck downwardly actuates the wheel and causes the leading portion of the tape to be peeled back from the strip and adhere to the incoming portion of the tape, thus surrounding the neck of the balloon.

Abstract: A foil applicator for applying decorative film from transfer foil to contoured edges, contoured serpentine edges and other edges of workpieces.The applicator includes a transport block having a face of substantially the same contour as the edge of the work piece with a heating means for the transport block, and a hammering means having a face of substantially the same contour as the edge of the work piece and being in close proximity to the transport block.

Abstract: A method and apparatus is provided for gripping a strap segment with two gripping members, for moving the gripping members together in a closed path to form a primary loop in the strap around at least one of the gripping members, and for feeding the strap to expand the primary loop to an expanded loop having a larger size for accommodating an article to be bound by the strap.

Abstract: A method and apparatus is provided for securing together overlapping portions of a thermoplastic strap loop around an object. After the strap is fed to form the loop, the upper strap portion is restrained while pulling the strap trailing portion to tension the loop. Lengths of the upper and lower strap portions are then gripped together in face-to-face contact to hold the loop in tension. The trailing portion is severed from the loop lower strap portion, and the restraint of the upper strip portion is terminated. A heating member is extended between the upper and lower strap portions in a direction generally parallel to the strap length. The upper and lower strap portions are pressed against the heating member to melt regions of the strap. The heating member is withdrawn, and the melted regions are pressed together as the melted regions solidify to form a joint. Included in the apparatus are coacting first and second gripper means, an anvil, a cutter, and a heating member.

Abstract: The taping unit has two positioning pins protruding outward from opposed sides of the taping unit. The head structure of the machine has supporting arms having longitudinal guides to accommodate and allow to slide said positioning pins of the top taping unit. Locking pins associated with said arms engage with the pins to allow stopping and locking the top taping unit. A housing recess for the bottom taping unit is provided in the box supporting base and has a pair of side shoulders containing pairs of recessed seats opening upward in which are accommodated the positioning pins of the bottom taping unit.

Abstract: A device adapted for applying L-shaped lengths of pressure sensitive adhesive coated tape on the peripheries of boxes moved past the device and for cutting the applied lengths of tape from a supply length of tape on the device, in which the mechanism for cutting the tape moves a cutting edge by which the tape is cut at about the same speed that the tape is moving in the longitudinal direction of the tape during engagement of the cutting edge with the tape.

Abstract: Apparatus for applying tape to a forwardly traveling carton includes a first projecting tape applicator which lies in the path of carton travel. As the carton strikes the first applicator, tape is applied to the carton front panel, the traveling carton depressing the applicator to allow it to apply and wipe tape around the corner formed by the front panel and onto a horizontal panel. A push finger carried on the tape applicator engages for a time with a tape cutter. On engagement of the push finger with a cam near completion of unit depression travel, the finger disengages the cutter and releases it to sever a tape length from the tape supply. A roller in the depressed applicator unit wipes the severed tape length along the horizontal panel for the length that the tape extends along the panel. A second tape applicator unit which moves from projecting to depressed position in tandem with the first unit is located downstream of the first applicator.

Abstract: A method and apparatus for feeding and tensioning strap in a strapping machine is provided. The apparatus includes a rotatable feed wheel and means for rotating the feed wheel, a first pinch roll associated with the feed wheel, and a first strap pressing means for moving the pinch roll between a strap engaging position and a position wherein the strap is not engaged. Also provided is a rotatable take-up wheel and means for rotating the take-up wheel in a direction opposite to the feed wheel rotation. A second pinch roll is provided adjacent the take-up wheel and is movable between a first position for engaging the strap and a second position wherein the strap not engaged. A high tension member is mounted for rotation between the feed wheel and take-up wheel. The high tension member defines a slot for accommodating the strap and defines a strap engaging surface on the periphery of the high tension member at an end of the slot.

Abstract: Disclosed is a binding machine for binding a bundle of linear members such as electric wires. The binding machine has a drum-like rotary member mounted for rotation in one direction. The rotary member has a notch extending radially inwardly to the area around the center thereof such as to provide a substantially U-shaped work holding portion. The rotary member further has a tape guiding portion extending radially outwardly therefrom and provided with a pair of guide pins which are spaced in the radial direction of the rotary member. A cutting blade is disposed between two concentric circles along which the guide pins move when the rotary member rotates. The cutting blade is directed counter to the direction of rotation of the rotary member. A tape roll holding means is mounted on the frame and adapted for holding a tape roll such that the leading end of the tape extracted therefrom is lead to a position in front of the radial opening of the tape holding means.

Abstract: A tool for the rolling of a metal foil onto the edge of a glass article in a wrinklefree manner comprises an elongated handle having a blade at one end of a guide path for the foil which peels the masking strip away from the adhesive layer of the foil and a pressing pin at the opposite end of the guide path which presses the foil against the edge of the glass.

Abstract: A process and apparatus for the production of laminated sheath cables having improved close contact between a laminated tape layer and the core of the cable. The tape is longitudinally wrapped around the cable with portions of the tape overlapping. The assembly is then heated and passed through a set of pressing rollers disposed at a single pressing position. The rollers are at least three in number. The arc length of each roller is determined by dividing the total outer circumference of the assembled tape and cable core by the number of rollers.

Abstract: An inlet applying roller and an outlet applying roller are elastically urged to project, at rest, from a casing which may be fixed to a sealing machine. The inlet applying roller is rotatably supported by support arms, which are movable along path defined by shaped windows engaged with a fixed pivot, and the outlet applying roller is rotatably supported by lever arms rotatable about a fixed fulcrum. Said support arms for the inlet and outlet rollers are kinematically connected to the support lever arms of the outlet roller so that the withdrawal movement of the inlet roller is accompanied by a simultaneous withdrawal movement of the outlet roller and the successive coming-out movement of the inlet roller is made dependent on a simultaneous coming-out movement of the outlet roller. A cutting blade is arranged between said rollers to cut the tape between subsequent cartons.

Abstract: From a casing destined for the fixing to a sealing machine project, at rest, an inlet roller and an outlet roller, which the same carton to be sealed forces to return into the outline of the casing during their advancement from one to another end of the casing. To the inlet roller is supplied an adhesive tape, which the same carton picks up and causes to adhere to the front wall, the adjacent horizontal wall and the rear wall by means of said inlet and outlet rollers. A cutting blade is arranged between said inlet and outlet rollers and is provided with suitable actuating means, which cause it to carry out a rapid run of cutting of the adhesive tape after the rear wall of the carton has overcome the blade a prefixed length.

Abstract: The machine comprises a support and advancement base for the cartons, a pair of mutually approachable conveying units and a vertically movable upper taping head. The movements of the taping head and of the conveying units are controlled by sensing members inserted in said support base.

Abstract: A system for wrapping a plurality of objects with an adhesive tape including yieldable support flaps for applying the tape and delivery means for periodically delivering a predetermined length tape to the flaps.

Abstract: A carton support base is formed by a rectangular frame, a succession of idle transversal rollers surrounded by said frame, and vertical legs passing through the frame and clamped thereto in adjustable position. From the sides of the frame there extend upwards a pair of vertical columns, which are releasably fixed to support brackets of limited vertical extension. The legs and the column can thus be removed to limit the overall size of the taping machine during transport. In addition, two taping machines can be superimposed to one another in overturned condition to form a "doubled" machine, which is able to apply adhesive sealing tapes to very high cartons.

Abstract: A number of elongate articles such as slide fasteners are discharged from a discharging mechanism and placed on a length of a band web which has been supplied from a reel on a bundle tray by means of a feed mechanism. The length of the band web has a free end and an opposite end gripped by a gripper mechanism. End portions of the length of the band web are ultrasonically fused to each other by a fusing mechanism constituted by an ultrasonic horn and an anvil. The opposite end of the length as it is gripped by the gripper mechanism is cut off by a cutter mechanism to form a band bundling the elongate articles, which are then discharged by the bundle tray.

Abstract: Apparatus and method for dispensing and applying copper foil to an edge and/or periphery of stained glass. The apparatus includes a horizontal base having a turntable, applicator platform, and dual adjustment applicator head mounted thereon. The applicator head includes a vertically adjustable foil support and a vertically adjustable guide bushing to permit the centered or uniformly offset application of the copper foil to the glass.

Abstract: The machine is provided with a carton support and advancement base and a sealing head superimposed to said support base and vertically displaceable with respect to the same. In order to adjust automatically the height of the sealing head to the variable height of the cartons there are provided sensing means mounted on said support base in such a position as to be engaged by the carton bottom to cause the consequent rising of the sealing head from a minimum-height position.

Abstract: The machine has a pair of belt-driven conveying units, which may be approached from opposite sides to the carton sides. For said units there is provided a displacing, guiding and driving system, which is simple and of reduced size and allows a very good engagement of the belts with the carton sides, particularly making easier the inlet and the outlet of the same cartons.

Abstract: An apparatus for automatically sealing random sized cartons having directly connected and positive acting arm control mechanisms acting on both ends of each arm to provide pure transverse motion of the side arms. The apparatus also includes novel lift means for raising and lowering the sealing means and preventing any wobble or lateral movement thereof. Means are provided for synchronizing the operation of both mechanisms.

Abstract: Two belt conveying units, which can be positioned at adjustable mutual distance, receive the belt driving movement by a transmission comprising conical gears slidingly mounted on a motorized shaft with polygonal cross-section situated at the outlet ends of said units. The above mentioned conical gears are provided with vertical outlet shafts, which simultaneously act as driving elements for the belts and as rotation pins for the support structures of the same belts.A threaded shaft for spacial adjustment of the conveying units and a transversal guide system formed by sleeves of limited extension slidingly mounted on a single guide are situated in a same vertical plane at the inlet ends of the conveying units.In addition to the motorization, the conveyor adjustment and the guide, there are thus assured limited rotary movements of the two units, which allow a suitable engagement of the belts with the carton sides for their whole path through the machine.

Abstract: Thrust members, for example idle rollers, supported by the taping head and disposed at the two sides of the carton support base, are approachable each other beginning from a mutual maximum removal position to exert opposite pressures on the carton sides, in order to limit the width of the upper longitudinal slot to be sealed. Preferably, the thrust members are firstly brought near the carton sides under elastic thrust and then pressed against them under pneumatic thrust.

Abstract: An apparatus for applying a strip of sealing tape to seal the bottom flaps of a low profile five panel carton comprising a frame structure defining a generally horizontal carton transporting surface; a tape applying means mounted to said fame structure; a bottom trailing tape engaging wipe down means; a directing means mounted to said frame structure for directing a trailing end portion of the strip of tape onto the top surface of the main panel of the carton adjacent the vertical surface of a trailing side panel and a top trailing tape engaging wipe down means mounted to said frame structure.

Abstract: The apparatus forms fiberboard hollow ducts from fiberboard and comprises means for collapsing or partially collapsing the fiberboard into a flat collapsed fiberboard or partially collapsed fiberboard for advancing the collapsed or partially collapsed fiberboard through a preheating and heating stage while heat sensitive tape is applied to the linear seam of the advancing fiberboard. After tape is applied, means for applying pressure and cooling operate to permanently set the tape.

Abstract: The invention relates to processes and devices for automatically depositing and pressing continuous tows in containers moved to and fro on a traversing device, wherein the start of the tow is transferred via a chute to a catch box on the container and is retained there, the container is weighed during each traversing movement because of the extension of a weighing platform and, when the nominal weight is reached, the fed tow is held and severed in a cutting and fixing device, the tow ends obtained are fixed and marked, and the tow end belonging to the deposited material and the start of the tow are introduced into the full container from the catch box.

Abstract: An apparatus for heat sealing together layers of strap of thermoplastics material, wherein at least one thin flat electrical heating element is supported under tension and between the layers of strap and the layers of strap are pressed together with a fusing pressure by at least one resilient pressure pad. The heating element, a support for the heating element and the resilient pressure pad form a heating and fusing assembly which is moved in unison relative to the layers of strap so that in use, the heating element moves between the two layers of strap generally in a longitudinal direction thereof.

Abstract: Disclosed is a machine for automatically banding particularly linear objects in groups with strap-type banding elements having interlockable male and female members at one and the other ends thereof respectively, which comprises a pistol-shaped machine body and an operation lever provided to a grip handle thereof and with which, when the operation lever is triggered, each banding element loaded on the machine body is fed forwardly in the machine body, applied about a group of objects to be banded and received on a front end portion of the machine body and then fastened with its male and female members interlocked to accomplish banding, the machine being characterized by comprising a pusher member driven through triggering of the operation lever to move in a guide path in the machine body from a rear end portion to a front end portion of the machine body while pushing a banding element, a stopper for fixing an end portion of the banding element at a front end portion in the guide groove during a banding operat

Abstract: Apparatus for producing reinforced plastic sheets and reinforced plastic sheet laminate structures on a high speed continuous basis and which sheets and laminate structures may have widths ranging from relatively narrow to very wide. The apparatus comprises a means for bringing one or more layers of resin impregnated, fiber-containing, reinforced plastic composite material into contact with each other or into contact with surfaces of one or more endwise abutted relatively flat panels.

Abstract: An apparatus for C-folding a running length of a covering web such as a polyethylene ribbon about a longitudinally flexible article such as a running length of a core web for making disposable diapers or a stream of longitudinally spaced discrete core segments of such a core web; i.e., a stream of absorbent cores for disposable diapers. The apparatus effects folding each longitudinal edge portion of a covering web downwardly and inwardly about an adjacent longitudinal edge region of the article as the web and the article are forwarded through the apparatus. Each longitudinal edge portion is so folded intermediate a transverse turning member which it passes under, and an oblique turning edge disposed downstream therefrom and over which it passes; and the longitudinal edge portions of the running web and the adjacent longitudinal edge regions of the article become juxtaposed upon passing over their respective oblique folding edges.

Abstract: An apparatus for the application of an adhesive film strip about the edge of a shaped part of sheet metal comprises a pair of application roller which rolls on the adhesive tape about the metal sheet edge, imparting to the strip a U-shaped cross section. The adhesive film strip is originally on a carrier tape and is on a storage reel from which it is drawn off by conveying rollers. After being separated from the carrier tape, the adhesive film strip is fed via free-wheeling pre-folding rollers to a pair of application rollers, and the carrier tape is removed by means of further conveying rollers. The pair of application rollers and the pre-folding rollers can be swivelled together about an axis extending parallel with the shafts of the application rollers, and are at the same time resiliently displaceable in the direction of this axis. The distance of the application roller shafts from the said swivelling axis is adjustable in order to achieve a leading or a trailing run.

Abstract: A label applicator for applying labels to articles which are moved along an article path comprising a conveyor having first and second conveyor sections on opposite sides of the article path and a label dispenser for dispensing labels onto the conveyor. The conveyor conveys the labels to a label retaining station at which the label spans the space between the first and second conveyor sections. An article to be labeled is moved along the article path between the first and second conveyor sections so the article contacts a central region of the label as it passes through the label retaining station. This adheres a central region of the label to the article. The end portions of the label are pressed against the article downstream of the label retaining station.

Abstract: The apparatus forms fiberboard hollow ducts from fiberboard and comprises means for collapsing the fiberboard into a flat collapsed fiberboard means for advancing the collapsed fiberboard through a preheating and heating stage while heat sensitive tape is applied to the linear seam of the collapsed fiberboard. After tape is applied, means for applying pressure and cooling operate to permanently set the tape.

Abstract: Fabric loops, intended for attachment to articles of clothing for example, are fabricated from a tape the free end of which is sequentially formed into a loops which are permanently closed. To form the loops, a continuous tape is delivered into a track which doubles back on itself whereby the advancing free tape end will overlap a portion of the tape, and the tape will subsequently be cut and the overlapping portions bonded together to complete a loop.

Abstract: This invention discloses apparatus for binding an article, such as a pack of bank notes, with a tape in a binding position. For this purpose, with rotation of a rotating member, the tape is supported by tape loop supporting pins and is wound to form a loop before a binding operation. The article is pushed into the loop and pressed before the tape is wound around the article. The tape supporting pins are retracted to disengage from the loop. The tape is drawn in a direction opposite to the supplying direction so as to be wound tightly around the article, and the trailing end of the tape is cut. The cut end of the tape is adhered to an adjacent portion of the tape. In this manner, tape binding is completed.

Abstract: An adhesive web is to be pressed on to the edge of a shaped sheet metal part, so that the web portion on the metal part has a U-shaped cross-section. To this end, the adhesive web is first peeled off a carrier tape and is then folded with the aid of a deflecting and pre-folding roller having a profile whose cross-section is a wide V. The pre-folded web is then folded further continuously in a funnel-shaped pre-folding channel.The sheet metal part whose edge is to be covered is then introduced with that edge, within the reach of the pre-folding channel, into the folded bend of the adhesive web, and both the sheet metal part and the web thereon are conveyed together by a pair of feed and press-on rollers which press the adhesive web on the edge and sides of the sheet metal part.

Abstract: An apparatus for sealing the foldable flaps of cartons. The apparatus includes an improved modular frame structure to support the sealing heads and the carton handling assemblies. The apparatus further includes an improved lift assembly to raise and lower the top sealing head assembly.

Abstract: Straps or belt loop strips are formed with the apparatus and method of the present invention by folding a strip of fabric about a strip of fusible material, threading the folded, combined strip back and forth between two side-by-side, counter-rotating cylinders so that, in the preferred embodiment, the strip forms a plurality of figure eight patterns over and between the two cylinders, and heating the cylinders to a temperature which is above the melting point of the fusible strip but below the scorching point of the material. The speed at which the cylinders are counter-rotated with respect to each other is chosen, in conjunction with the number of loops of the combined strip over the cylinders, to place the combined strip in contact with the heated surface for a length of time sufficient to accomplish complete fusing.

Abstract: A machine for wrapping a band around a stack of flat articles. A band guiding assembly and a clamp assembly are at a banding station. An end portion of a strip of banding material is advanced from the band guiding assembly to the clamp assembly, and a clamp mounted on the clamp assembly closes an end portion of the strip of banding material. The clamp assembly is separated from the band guiding assembly to provide an exposed section of the strip of banding material. The stack is advanced against the exposed section of the strip of banding material to draw the banding material around three sides of the stack. The section of the strip of banding material at the stack is cut to provide a second end portion for overlapping the first mentioned end portion. Glue is deposited on one of the end portions in position for overlapping by the other end portion.

Abstract: Mounted in tandem on an elongated frame, a plurality of applicator head assemblies affords a versatile machine for bonding a decorative coating even to a relatively complicated pre-shaped edge of a workpiece. Means on the head for accurately positioning a rotatable applicator wheel having a circumference of silicone rubber profiled to match the edge permits the wheel to urge the coating with precision and uniformity onto the contoured edge of the substrate. An external radiant heat source raises the temperature of the silicone rubber periphery which, in turn, transfers heat by conduction to a transfer foil, thereby releasing the foil carrier and bonding the decorative film to the substrate edge. Pressure applied by the wheel in the plane of the wheel creates a wheel flat resulting in increased contact area and dwell time, thereby enhancing bonding precision and strength.

Abstract: This invention discloses an apparatus for binding in cross shape an article such as a pack of bank notes with an elongate binding material such as a tape in a binding position. First, the article arranged in a first direction is pushed in the binding position and the article is then bound with the binding material. The trailing end of the binding material is cut and adhered to an adjacent surface of the binding material. When the first binding operation is completed, the bound article is removed from the binding position, being turned through 90 degrees in a manner to be arranged in a second direction perpendicular to the first direction. The article thus returns to the initial position. The article is pushed again in the binding position. Second binding is performed, accomplishing binding in cross shape.

Abstract: A device for applying a tape around one or more objects, in which first a pe consisting of two tapes welded together is passed in U-shaped fashion around the object or objects, thereafter the two tape portions extending beyond the object or objects are moved towards one another by means of movable tape strainers; thereupon one tape portion is melted through, bent over and superficially melted by a heating element forming part of a tape bending-over member; then the other tape portion is melted through to form tape end portions and superficially melted by said heating element and finally the latter tape end portions are bent over and welded to the former tape end portions in pairs by a second tape bending-over member; the two bending-over members so co-operating as to make the two weld joints between the respective tape end portions to lie in the plane of tape of which they form part.

Abstract: Apparatus (26) for taping bundles of wires (4) into compact sheaves (8) comprises first and second bundling rolls (28, 30) having cylindrical surfaces (36, 38) which are in contact in a nip zone (40). First and second tapes (42, 46) are fed towards the rolls on one side of the nip zone and extend through the nip zone. Wires (4) are presented to the rolls on the one side (52) and passed through the nip zone during rotation of the rolls (28, 30). Tape is applied to each bundle from opposite sides of the bundle. On the other side (54) of the nip zone the tape is cut between adjacent bundles by knives (60) on a cutting wheel (56). A plurality of taping devices (26) can be provided on a harness making machine (12) so that the completed harnesses (2) are taped at several locations (10) along their lengths.

Abstract: Described is an apparatus for the application of a thin non-woven web of glass or mineral fibers onto corrugated sheet perpendicularly to the corrugation which comprises a rectangular frame open at the top and bottom and having parallel vertical walls, wherein the frame is provided with wheels and supported on rails above the sheet material which is supported by a matrix on working-level above the floor and coated with a layer of a solidifying glue. An applicator plate is mounted vertically movable in guideways at two opposite walls of the frame and adapted with its bottom edge to follow the corrugations of the sheet to bring the fibrous web into close contact with the glue-coated sheet. Because of the delicacy of the fibrous web of material, the lower end of the applicator plate which is adapted to press the web of material against the sheet, must be rounded.

Abstract: A machine for making packages with labels is provided. The packaging machine utilizes a supply of packaging material in the form of a length of plain plastic tubing and a supply of labels in the form of a continuous strip thereof. In a previous cycle of the machine, the tubing was heat sealed along a transverse strip near the leading edge thereof. The strip is subsequently advanced a predetermined distance between a first set of jaws which close, with a first sealing wire carried by one of the jaws then energized to seal a leading edge of the tubing which will form the next package. A knife severs the tubing below that seal and the upper edges of the severed section which has been advanced are engaged by clamps. These move apart with the jaws to open the upper edges, thereby enabling an article to be dropped into the resulting pocket in the severed package section. The jaws then close once again and a second sealing wire below the clamps seals the upper edges of the severed section.

Abstract: A binding machine for the application of a strip of flexible material around the outline of thin articles, particularly for edging parts for boots and shoes, comprising a fork with an alternating movement for folding the strip partly above and partly below the outline of a thin article, means for causing adhesive to be placed between the said strip and the said article, and a pressure and transportation group for the intermittent pressing of the strip against the article, after the folding operation performed by said fork, and for sending said article forward as it has been edged, said pressure and transportation group comprising a hammer shaped part and an anvil shaped part mounted on a hollow shaft oscillating about its axis, which parts are caused to move the one towards the other and vice versa by a rod placed in the hollow shaft and movable in a reciprocating way.

Abstract: Apparatus is disclosed capable of wrapping both cold-applied and hot-applied strips of sheet material in tape form around a pipe or conduit having a generally circular cross-sectional external shape. The apparatus includes a frame having a desired number of frame cross members for structural support and having a hinged rotatable frame portion; a plurality of guide roller assemblies connected to the frame; a guide roller tensioning assembly; a sheet material feeding assembly; a sheet material tensioning assembly; a guide roller angular adjustment assembly, adjustable to vary the angle of the guide rollers with respect to the conduit being wrapped for varying the amount of sheet material overlap; a cold-applied tape backing material take off and wrapping assembly, and a burner assembly, alternatively attachable to the frame instead of the cold-applied tape backing material take off and wrapping assembly, when hot applied tape is used.

Abstract: A binding machine having a base and a binding arm pivoted to the base, for tightly binding articles to be inserted between the base and the binding arm with an adhesive tape which is fed from a tape reel to a tip portion of the binding arm, by swinging down the binding arm toward the base.

Abstract: Apparatus for joining the aligned edges of superposed plies of sheet material by means of an adhesive joining strip comprises a retractable nozzle for applying adhesive to the strip, and a forming plate which is curved for guiding the strip towards said edges and which defines a channel for bending the strip into U shape so that the edges come to lie between the limbs of the U.