DE102006026395A1 - Manufacturing plastic net forming part of known self-adhesive wound dressing, welds plastic projections to net intersections and heats to form mushroom ends - Google Patents

Abstract

A relevant dressing is described in . The plastic projections (30), held in a part carrier (22) are introduced to the plastic net (24) as an arrangement or pattern. They are brought together, welding the plastic projections to crossing points of the net. The projections are plastic rods or balls. The plastic net, with the welded plastic projections, is then led through rollers (28, 29). This forms a mushroom-shaped flattening on the projection ends remote from the net. A sorter and filler (21) first introduces the projections into the part carrier. The latter is a roller (22), the projections being inserted into its outer surface. Hot-element-welding completes attachment with the net. Alternatively vibration-, ultrasound- or laser welding is used. Independent claims are included for the following: (A) Corresponding manufacturing equipment; (B) and the competed net with mushroom projections.

Description

From the German patent DE 101 53 012 C1 For example, a flexible clamp dressing is known that has an adhesive surface for adhering to the skin. At least partially, a reinforcing support in the form of a plastic net as a plastic mesh is present on the surface facing away from the skin. At the crossing points in the plastic mesh fasteners for holding tensioning threads are attached.

Around To make such a plastic net, one could think of it Plastic injection molding process, in particular a so-called dipping edge process use. A disadvantage of this method are the high tooling costs and the requirement for every material thickness to have to keep a separate tool. Also, that's the procedure not for the production of a very fine-meshed plastic net suitable; Even a continuous production is not possible.

Further could one should consider to produce such a plastic net with a plastic dosing. Indeed Here is a complex hardening process perform, and the plant as a whole and process monitoring are very expensive.

Of the Invention is based on the object, an easy to be performed Specify a method for producing such a plastic network. there the plastic net may be a plastic fabric, the one by two intersecting, lawally entwined groups of threads fabricated structure is, or around a plastic net, a through Lichen or knot formed meshwork forms. Furthermore, can the plastic net is a cast mesh.

to solution This object is achieved in a method for producing a plastic net with protruding from the network level at crossing points in the plastic network Plastic elements according to the invention, the plastic elements in a parts carrier in an arrangement corresponding to the crossing points in the plastic net introduced, and there are merged the parts carrier and the plastic net and the plastic elements welded to the plastic net at the crossing points. there the plastic elements are arranged in the parts carrier so that they each with a single crossing point or each with several Weldable crossing points are; in the latter case is then in each case a plastic element with welded at several intersection points.

One An essential advantage of the method according to the invention is that as a starting material on in any size, mesh size and thread size available in the market Plastic meshes. The same applies with regard to the plastic elements, as Rod or round material or rolls and balls in manifold Form available in the market. These starting materials are joined together by welding to a Plastic net with protruding from the mesh level fasteners to win.

When it is considered particularly advantageous if in the method according to the invention used as plastic elements plastic pins or plastic balls be because such plastic elements after attachment by welding especially easy to deform.

at a particularly advantageous embodiment of the method according to the invention the plastic net with the welded plastic elements gets through a roller arrangement led, in the plastic elements under heat and pressure at their from the plastic network opposite side mushroom-shaped be flattened. This way is very easy make a plastic net with fasteners that on their nub-like design or flattened mushroom-shaped so they are used to hold tensioning threads in a flexible clamping bandage are particularly well suited.

Around the inventive method especially economical carry out to be able to be advantageously the plastic elements by means of a Sorting and filling device introduced into the parts carrier.

When parts carrier Advantageously, a roller is used, on the outer circumference of the plastic elements be introduced.

at the welding method according to the invention can advantageously different welding methods are used.

When advantageously usable heating element welding (see, for example, the German patent DE 34 41 988 C1 and the German Offenlegungsschriften DE 100 19 300 A1 . DE 102 35 892 A1 and DE 199 30 070 A1 ) are the joining partners, the plastic net as, for example, plastic fabric / grid and the fasteners driven, for example in the form of plastic balls / pins against a heating element. Subsequently, under Anwärmdruck the adjustment process is started to compensate for tolerances and to achieve a uniform contact surface to the heating element. In the warming phase, the melt cushion is formed almost without pressure. A subsequent joining pressure adds the joining partners together. After a cooling process, both joining partners are firmly connected. In order to avoid stringing, a non-stick coating (eg Teflon) should be used on the heating element.

at be used also advantageous vibration welding the two joining partners (plastic mesh mesh) and fasteners (plastic balls / pins) under joining pressure rubbed against each other. As a result, the parts to be joined are plasticized. One sustained holding pressure ensures a Sinking of the two joining partners each other. After a short cooling phase Both partners are material-locking connected with each other.

When also advantageously usable laser welding (see, for example, the German Offenlegungsschriften DE 42 25 679 A1 and DE 44 32 081 A1 and DE 102 35 892 A1 ), the two joining partners are aligned, that is fixed under low contact pressure. A two- / three-dimensional clocked laser head is positioned above the weld. The emerging laser beam penetrates the transparent joining partner (plastic mesh / mesh) and heats the non-transparent or less transparent joining partner (plastic balls / pins). There, the laser beam is converted into heat, which leads to plasticization of the non-transparent / less transparent joining partner with simultaneous volume expulsion. This budding heats the transparent joining partner and also plasticizes this. After a short cooling phase, the welding process for each one fastener (plastic ball / pin) is completed. The laser clocks to the next weld, or is guided by mirrors to the next weld. This process can be carried out simultaneously or quasi simultaneously for individual spot welds as well as for multiple spot welds. The method requires a coloring of a joining partner (preferably plastic balls / pins) to ensure the required lack of transparency.

At the also be used advantageously ultrasonic welding the two joining partners (plastic mesh / grid and plastic balls / pins) aligned. By flat or conical / stabförmger Sonotrode the respective welding point is controlled. After pressurization on the joining partners an ultrasonic vibration is coupled into the joining partners. The joining partner are set in vibration. The vibration is converted into heat and leads for plastification of both joining partners. After cooling are both material-locking connected with each other.

All o. g. welding processes are well known both in theory and in practice and are used extensively to connect plastic parts worldwide used various forms. The welding process themselves are for Any scope is available and no longer required become. This means that it is for carrying out the method according to the invention in terms of welding only the constructive and procedural fine-tuning needed to achieve satisfactory results.

All above-mentioned welding methods are in principle for producing a plastic net for a flexible clamping bandage according to the German patent specification DE 101 53 012 C1 applicable. All these methods offer the advantages of continuous production, high flexibility of the process, low environmental and process monitoring and thus a high cost savings compared to the production by injection molding

Opposite one Dosing process (application of fasteners on plastic mesh / mesh) offer the welding process just as huge savings on the part of process monitoring / parameter monitoring.

O. G. welding processes offer about it In addition, the advantage that all product components as semi-finished products today available in the market are. There are both plastic fabric and plastic meshes in all for the medical field suitable materials available, and there are also for the appropriate fasteners suitable components such as Rod material (pins) and plastic balls in ground and uncut form marketable.

Another advantage of welding processes is that they can react quickly and comprehensively to market changes. It can almost any patch sizes according to the DE 101 53 012 C1 be produced in almost any strength and strength of different characteristics for a wide variety of applications. For this purpose, only a changeover to the respective welding device is required. Another advantage of welding technologies is that the process supply of heat with pressurization - already exists and thus the flattening of plastic balls / pins can be easily integrated into mushrooms / nubs listed above.

The invention is further based on the object to propose an arrangement for carrying out the above-mentioned method according to the invention, which is characterized by a simple structure and a simple adaptation to differently designed and dimensioned, with plastic elements picking plastic nets.

to solution this object is according to the invention the part carrier movable in such an arrangement and has receiving means for the plastic elements, wherein the receiving devices in a distribution accordingly the junction points are provided in the plastic net; a Kunstoffnetz feeder has a pressure element with which the plastic net against the parts carrier pressed is, and it's a welding device provided in the pressed against the parts carrier plastic net and the plastic elements in the parts carrier welded together become.

One An essential advantage of this arrangement is seen in the fact that they comparatively easy to be produced with plastic networks different dimensions both in terms of the mesh size of the plastic network as well as in terms of the size of the plastic net can be adjusted in total, in each case essentially exchanged only the parts carrier and the welding device with regard to their welding head is adjusted.

When Particularly advantageous it is considered when the parts carrier a Roller with distributed on its circumference arranged receiving devices is because with it the arrangement spatially can be made compact.

Also it is advantageous if, in such an arrangement, the sorting and filling device with its flat discharge opening the circumference of the roller opposite is arranged such that the flat discharge opening parallel extends to the axis of the roller. The pressure element is more advantageous Wise.

The welding equipment can in the inventive arrangement be formed differently. Both a heating element welding device is advantageous or a vibration welding device as well as a laser welding device or an ultrasonic welding device.

The Roller assembly for flattening the welded plastic elements can in the inventive arrangement also be designed differently; as particularly advantageous it is considered that the roller assembly consists of two rollers, wherein the side of the welded plastic elements of the Plastic net facing pressure roller is heated.

The invention further relates to a plastic net with protruding from the mesh level plastic elements, as described in the above-mentioned German patent DE 101 53 012 C1 is described; It is based on the task of designing this network so that it is relatively easy to produce.

to solution This object is in the plastic net according to the invention, the plastic elements welded to the plastic net.

In In a particularly advantageous embodiment, the plastic elements mushroom-shaped at their free ends flattened.

to further explanation the invention is in

1 an embodiment of a method according to the invention or with the inventive arrangement using plastic balls as plastic elements produced plastic net in the form of a plastic fabric in a side view and a plan view,

2 an enlarged view of the detail A after 1 .

3 an embodiment of a process according to the invention or with the inventive arrangement using plastic pins as plastic elements produced plastic net in the form of a plastic fabric in a side view and a plan view,

4 an enlarged view of detail B after 3 and in

5 An embodiment of an inventive arrangement for producing the plastic network according to the invention.

The 1 shows a plastic net 1 as plastic fabric in an unqualified size. Plastic elements are here as plastic balls 2 executed in crossing points 3 (see the detailed view A according to 2 ) with the plastic net 1 are welded. Both the plastic net 1 as well as the plastic balls 2 can vary in size, strength, strength, material and fineness. The decisive factor here is in particular the requirement of physicians (consumers) if the plastic net 1 to be used as a material for a flexible clamping bandage. Generally speaking, the smaller the wound, the finer the plastic mesh 1 and plastic balls 2 perform. With 4 is a flattened portion of the plastic balls, which is generated under heat and pressure; the plastic balls 2 are thus mushroom-shaped flattened to a tensioning thread 5 when using the plastic net 1 in a flexible clamping bandage a grip in the tension by means of the plastic balls 2 by means of the tensioning thread 5 to give.

Basically the geometry of the spherical shape alone sufficient to create a tension by means of tensioning threads perform. However, since this is a medical device product occurs an increased Safety in the foreground. An unintentional jump off the tensioning sutures of the fasteners must not be made. This is preferred achieved in that by pressure and Temperaturbeaufschlagung the plastic balls flattened on their side facing away from the weld are.

In the 3 respectively. 4 illustrated further embodiment shows a plastic net 10 in unmaßstäblicher size, in the plastic elements in the form of plastic pins 11 are used. Both plastic net 10 as well as the plastic pins 11 can vary in size, strength, strength, fineness and material arbitrarily according to the requirements of doctors, if the plastic net 10 is used for a flexible clamping bandage. The plastic pins 11 are at one or more crossing points 12 in the plastic net 10 with this welded and under heat and pressure to form flats 13 flattened mushroom-shaped. This will be a tensioning thread 14 given a stop when the plastic net 10 Part of a flexible clamping bandage is and to close a wound by means of tensioning threads 14 serves.

When used in a clamping bandage, the simple cylindrical geometry of a plastic pin would 11 Although basically allow a tension, but could not be permanently ensured due to the tendency to tilt a reliable tension. Both an increased resistance to tipping and a secure tension with the tensioning thread 14 are achieved by mushrooming the plastic pins by applying heat and pressure.

As the 1 and 3 are in this example at every fourth intersection 3 respectively. 12 the plastic nets 1 respectively. 10 Plastic elements 2 respectively. 11 welded. The needs of the market and thus the requirements of a clamping bandage like in DE 101 53 012 shown, vary widely. Both the plastic net and the dimension of the flats 4 respectively. 13 Accordingly, they can be very different. This means that a plastic element (plastic ball, pin) can be welded directly to one and thus at every n-th crossing point of the threads of the plastic net, as well as over several intersections of the threads of the plastic fabric or network can extend. The finer-meshed the plastic mesh / mesh, the more strongly the weld points of the plastic elements overlap the respective crossing points of the plastic mesh / mesh.

On the basis of in 5 illustrated embodiment of an arrangement for producing the plastic network according to the invention, the sequence of the manufacturing method according to the invention is explained:
In a preferred embodiment, round material in polypropylene, polyamide or polyethylene or also round material from other materials suitable for welding technology in medicine is cut into plastic pencils. These plastic pens are made by means of a sorting and filling device 21 in a part carrier in the form of a roller 22 filled so that the distances of the now upright plastic pins corresponds exactly to the desired distance of the plastic pins on the plastic mesh. Via a feeder 23 becomes the plastic net 24 against the face of the lined plastic pins in the roller 22 guided. A short-term heating of plastic net and front side of the plastic pins by means of a heater 25 causes both components to melt, so that fabric threads of the plastic net and the front side of the plastic pins weld into a homogeneous unit. This is ensured by a pressure roller 26 for the required contact pressure at the end of the melting process and flattens out the swelling melt. The heater 25 and the pinch roller 26 thus form a Heizelementeschweißeinrichtung.

About a cold pulley 27 becomes the plastic net 24 deflected by the now welded plastic pins and by two pressure rollers 28 and 29 guided. The pressure roller 29 is heated and causes the pre-welded plastic pins are flattened or truncated mushroom-shaped or knob-shaped on the opposite side of the weld by applying temperature and pressure.

The depiction of detail C reveals that the plastic net 24 with the welded plastic pins 30 from in the illustration left between the pressure rollers 28 and 29 enters. These are from the heated pressure roller 29 the plastic pins 30 melted at their lower ends in the drawing and then under pressure of the pressure rollers 28 and 29 flattened mushroom-shaped.

In a corresponding manner, with the arrangement according to 5 Plastic balls are welded as plastic elements to a plastic net and then flattened.

Both methods, both the use of plastic pins and plastic balls, allow a secure connection to the plastic net. They also allow due to the mushroom-shaped flattening secure guidance of tensioning threads when using the Kunststoffnet zes in a clamping bandage and prevent slipping of the tensioning threads and thus a dissolution of the clamping bandage.

Claims (20)

Method for producing a plastic net with plastic elements protruding from the net plane, characterized in that • the plastic elements ( 2 ; 11 ; 30 ) into a parts carrier ( 22 ) in an arrangement in the plastic net ( 1 ; 10 ; 24 ) and • the parts carrier ( 22 ) and the plastic net ( 1 ; 10 ; 24 ) and the plastic elements ( 2 ; 11 ; 30 ) with the plastic net ( 1 ; 10 ; 24 ) at crossing points ( 3 ; 12 ) are welded. A method according to claim 1, characterized in that • plastic elements as plastic elements ( 11 ) or plastic balls ( 2 ) be used. Method according to claim 1 or 2, characterized in that • the plastic net ( 24 ) with the welded plastic elements ( 30 ) by a roller arrangement ( 28 . 29 ), in which the plastic elements ( 30 ) under heat and pressure at its from the plastic network ( 24 ) are flattened mushroom-shaped side. Method according to one of the preceding claims, characterized in that, • the plastic elements ( 30 ) by means of a sorting and filling device ( 21 ) in the parts carrier ( 22 ) are introduced. A method according to claim 4, characterized in that • as a part carrier, a roller ( 22 ) is used, at the outer periphery of the plastic elements ( 30 ) are introduced. Method according to one of the preceding claims, characterized in that, • the plastic elements ( 30 ) with the plastic net ( 24 ) are welded by means of heating element welding. Method according to one of claims 1 to 5, characterized that, • the Plastic elements are welded to the plastic net by means of vibration welding. Method according to one of claims 1 to 5, characterized that • the Plastic elements are welded to the plastic net by laser welding. Process of claims 1 to 5, characterized that • the Plastic elements are welded to the plastic mesh by means of ultrasonic welding. Arrangement for performing the method according to one of the preceding claims, characterized in that • the component carrier ( 22 ) is movable and receiving devices for the plastic elements ( 30 ), wherein the recording devices in a distribution corresponding to the crossing points ( 3 ; 12 ) in the plastic net ( 24 ) are provided, • a plastic mesh feed device a pressure element ( 23 ), with which the plastic net ( 24 ) against the parts carrier ( 22 ), and • a welding device ( 25 . 26 ) is provided, in which the against the parts carrier ( 22 ) pressed plastic net ( 24 ) and the plastic elements ( 30 ) in the parts carrier ( 22 ) are welded together. Arrangement according to claim 10, characterized in that • the parts carrier a roller ( 22 ) is arranged with distributed on its circumference arranged receiving devices. Arrangement according to claim 11, characterized in that • the sorting and filling device ( 21 ) with its flat discharge opening the circumference of the roller ( 22 ) is arranged opposite so that the flat discharge opening parallel to the axis of the roller ( 22 ). Arrangement according to one of claims 10 to 12, characterized in that • the pressure element a roll ( 23 ). Arrangement according to one of claims 10 to 13, characterized in that • the welding device comprises a heating element welding device ( 25 . 26 ). Arrangement according to one of Claims 10 to 13, characterized that • the welding equipment a vibration welding device is. Arrangement according to one of Claims 10 to 13, characterized that • the welding equipment a laser welding device is. Arrangement according to one of Claims 10 to 13, characterized that • the welding equipment an ultrasonic welding device is. Arrangement according to one of claims 10 to 17, characterized in that • the roller arrangement consisting of two rollers ( 28 . 29 ), wherein the side of the welded plastic elements ( 30 ) of the plastic net ( 24 ) facing pressure roller ( 29 ) is heated. Plastic net with plastic elements protruding from the lattice planes at points of intersection in the plastic net, characterized in that • the plastic elements ( 2 ; 11 ; 30 ) on the plastic net ( 1 ; 10 ; 24 ) are welded. Plastic net according to claim 19, characterized in that • the plastic elements ( 2 ; 11 ; 30 ) are flattened mushroom-shaped at their free ends.