FI59358C - VAERMEFOERSEGLINGSAPPARAT - Google Patents

Description

| · Α £ * »· 1 ΓβΙ μ1 * advertisement publication 46Γλ W (11) utlAggninqsskmft 59358 ^ Patent ayännatty 10 00 1931 -Pateat aeddelat" (51) Kv.ik./!w.ci. B 31 B 1/64 ENGLISH— FINLAND (21) »*» tw> uih «kw« u · —p »*« «tt» »ekMnf 770096 (22) HtkamltpUvt - Anaeknlnftdif 13 · 01.77 (23) AlkupUvI — GIMgh« tad «f 13.01.77 (41) ) Tullut | ulklMkal »BlMt offontllg 2U.07.77 PMMtl · rMttrihslHtu, (44)

Patent- och ragirterrtyralMn '' Araekan uthfd «d» utUkmtM pub0c «r * d 30.0U. 8l (32) (33) (31) Pyy4 * «y eweik *» · —i «| ird a priori '* 23.01.76 USA (US) 653882 (71) Moore Business Forms Inc., 1001 Buffalo Avenue, Niagara Falls,

New York 11 + 302, USA (72) John E. Traise, Niagara Falls, New York, USA (7U) Berggren Oy Ah (5U) Heat Sealing Device - Värmeförseglingsapparat The present invention relates generally to a heat sealing device and more particularly to such a device for locally heating the hot melt adhesive between overlapping layers of further movement forms.

The multiple layers of extension forms attached to the kit are often secured together with a hot melt adhesive that must be heated to activate it. For this purpose, continuation sheets are usually passed through some source of heat. Although such a heating method effectively activates the hot melt adhesive, it is expensive and inefficient mainly due to the waste heat energy caused by heating the entire mold. In addition, the form must be supported as it passes through the heat source. Such a support also heats up in this case, which may result in the web burning if extreme care is taken.

It is therefore an object of the present invention to provide an improved heat sealing device.

2 59358

Another object of the present invention is to provide a heat sealing device capable of sealing a plurality of continuous form layers together using as little thermal energy as possible to activate the hot melt adhesive while simultaneously supporting the movable form directly to a plurality of heating elements.

According to the present invention, a heat sealing device for further movement forms, in which the forms to be sealed are multi-layered and in which the rollers compress the layers together after heating, comprises a plurality of elongate heating elements arranged parallel to each other at a distance from each other. The device is characterized in that the elements are convex-curved between their opposite ends and support a longitudinal extension form above the elements for the local heating of the hot-melt adhesive interposed between the layers.

The heat sealing device according to the invention will now be described in more detail with reference to the accompanying drawing, in which Figure 1 shows a perspective view of the device according to the invention in connection with a continuation form, and Figure 2 shows a cross-section of the device along line 2-2.

In the drawing, the same and corresponding parts of different figures are denoted by the same reference numerals. The heat sealing device marked 10 comprises a plurality of elongate heating strips or elements 11 located parallel to each other and parallel to the direction of movement of the movement form F, as shown by the arrow in Fig. 1. The heating elements are spaced transversely apart and are mounted on a curved mounting plate which is substantially convex in shape, as shown in the figure. The heating elements or strips may be nichrome or other suitable electrical resistor. Slab 12 may be made of materials with low specific thermal constants, such as phenolic resin or ceramic, which are also electrically non-conductive and can be made into the desired shape. The guide plates 13 and 14, which are also made of materials having a low specific thermal constant, are attached to opposite sides of the mounting plate and extend upwards therefrom to form suitable guides for the movement form F. Such a form is shown in the drawing as having a two-layer structure, whereby its surface layer 14 is folded longitudinally along its center line onto the base layer 1535358. Such folding is usually performed by means of a gradually tapering folding plate, not shown, through which the flat paper web is drawn to fold it effectively along its longitudinal centerline. Of course, layers of other types of form bodies can also be heat sealed together using the present device without departing from the scope of the invention.

Hot melt adhesive spots 16 are placed adjacent to the transverse weakening lines 17 used in the mold to separate it into separate units U as the form passes through a tear-off machine or the like. The form shown in Figure 1 also has feed belts 18 and 19, each of which has spaced edge feed holes.

The strips can be detached from the web along lines of weakness 22 and 23. The adhesive stream 16a may be interposed between the overlapping feed belts inwardly of their feed holes, as shown in the figure, so that each unit forms an envelope closed along the adhesive spots 16 and the adhesive stream 16a on three sides and connected along a center line of weakness at the center fold line. Similar glue streams can also be used next to the stacked weakening lines 17 instead of glue dots 16. Once the overlapping layers of the motion form are attached to each other, the units U are separated to form an envelope that can be easily opened simply by removing the tear tape formed from the attached feed tapes and then peeling the layers apart to break the adhesive therebetween. As mentioned above, the longitudinal centerline along which the layers are folded may also comprise a line of weakness, so that the layers can be completely separated by tearing along such a line.

The device for pressing the folds of the mold together after the heating elements may comprise two cooperating pressing rollers 24 and 25 rotatably driven by a suitable device (not shown). The space between these rollers is in the same plane as the upper surface of the heating element paths at their end, so that the folded form can pass through this space as described below. Alternatively, compression plates (not shown) may be used instead of compression rolls to compress the folds together in a similar manner.

4 59358

After the pressure rollers is also provided with a pull pin feed apparatus 26 which is of standard design and comprises an endless moving belt having a feed holes 21 arranged at intervals corresponding feed pin 27, which engage into the holes for moving the folded sheet of Figure 1 in the arrow direction. This traction device may be part of a mechanical release mechanism normally used to move the form forward. The power control system 29 of the heating elements can be operatively connected to the speed control 31 of the release mechanism, as shown in the drawings, so that the feed power of the heating elements is increased / decreased according to the increase / decrease of the web speed.

In use, the folded form is moved forward by means of a draw pin feeder so that the form slidably engages the heating elements and passes through the space between the press rolls. The heating elements are arranged directly below the glue dots 16 and the glue stream 16a. If glue streams are used instead of glue dots 16, the heating elements can simply be arranged below them to melt and activate a portion of the transverse glue streams during web movements. Due to the connection between the system 29 and the speed control 31, the heating means heat up quickly, thus avoiding the waiting or "preheating" time required to perform the sealing from the minimum web speed to the maximum speed. The heating strips also maintain a resting state when the device is stopped, which keeps the sealing at a minimum level, thus substantially avoiding local burning of the web. The heating elements actually support the form as it moves forward. The adhesive dots 16 as well as the adhesive streams 16a are melted and activated in this way when the heating elements locally heat only the parts of the form against them. Due to the curved shape of the heating elements, the form moves forward in close contact with the heating elements. The retention net 28, which may be an open-loop Teflon-coated glass-fiber structure, may be placed over the entire curved surface of the heating elements. The folded web under the net is therefore kept in close contact with the heating elements due to both their curved shape and the retaining property of the net, which ensures an absolutely close sliding contact between the web and the heating elements. For example, the wrinkles of the form between the units U are smoothed by a net 28. As the form advances, it passes between the press rolls 24 and 25, bringing the heated web into close contact between its adjacent folded surfaces to terminate around the perimeter. The form then passes through a tear-off device or the like to separate the units U.

From the above, it can be seen that an economical and yet very efficient heat sealing device for continuation forms has been provided. The circumferential bonding of the folded layers is accomplished by a plurality of heating strips 11a arranged parallel to a curved mounting plate and forming a heating device from a source (not shown) for local melting of the heat sealing adhesive during between the beginning and the end. Forms are fed by conventional pin feeders, which may be integral with the present device or be part of an adjacent unit, such as a tearer or printing machine (not shown).

The web, the adhesive regions of which have been softened as described, passes from the heating region at the end of the heating elements through pressing devices which bring the thus heated web into close contact between its adjacent folded surfaces to complete the circumferential fixing step.

It will be apparent that the invention may be varied and modified in many ways within the scope of the foregoing description. The invention can therefore be applied in a manner other than that described above within the scope of the following claims.

Claims (4)

6 59358 A heat sealing device for further movement molds, wherein the sealable forms are multi-layered and in which the rolls (24, 25) compress the layers together after heating, the device comprising a plurality of elongate heating elements (11) arranged parallel to each other, characterized in that the elements (11) convexly curved between their opposite ends and supporting a longitudinal extension form (F) above the elements for local heating of the heat sealing adhesive (16) interposed between the layers. Device according to claim 1, characterized in that the convexly curved mounting plate (12) is arranged below the heating elements parallel to them and the upwardly extending guide plates (13) are arranged along opposite sides of the plate (12) to guide the mold as it moves the press rolls (24, 25). ). Device according to claim 1, characterized in that the heat-resistant open-loop net (28) is arranged above the heating elements (11) for pressing the form (F) against the elements as it passes under the net (28). Device according to claim 1, characterized in that the heating capacity of the heating elements is small and comprises a device (26) for advancing the continuation form (F) and a speed control connected to the device (26), the heating element being operatively connected to the speed control system. to increase and decrease the feed power of the heating elements (11) by increasing and decreasing the speed of the mold, respectively, thereby providing a substantially constant transfer of thermal energy to the adhesive at all mold speeds and without significant heat loss time.