DE4210066C1 - Fabric clip mounting - has injection moulding appts. to shape plastics component and be bonded to fabric at defined location within assembly - Google Patents

Abstract

Plastics component is initially formed by injection moulding with the lower tool in a sealed fit at the dividing plane of the injection mould at the bottom of the moulded component. After injection moulding, and partial cooling of the component, the workpiece fabric is laid in the tool assembly in a defined position, while the shaped component remains in the injection mould, with a lower projection portion. The lower tool is retracted from the lower side of the shaped component by the thickness of the fabric workpiece, for the fabric workpiece (19) and component to be bonded together within the closed tool assembly. Pref. adhesive is used to bond the shaped component to the workpiece fabric at the bonding zone between them. As the component is shaped by injection moulding, a lower projection portion is formed at the bonding zone, of a material which becomes a liquid adhesive through a friction welding action to give a hot bonding effect. USE/ADVANTAGE - For bonding plastic slips esp. of textiles to fabric materials for vehicle interiors and similar applications. Visible side of the fabric is undamaged and unchanged through the bonding action of the plastics component.

Description

The invention relates to a method and an apparatus for Attaching plastic parts to a lobed sheet material-formed workpiece, especially on textiles, according to the preamble of claim 1 and 6 respectively.

The US-PS 47 84 591 relates to a method for attaching Plastic parts on a textile good. With this procedure the textile good is defined in a position that is initially open Device consisting essentially of an upper and an Un ter tool exists, inserted. When installing on one side nes plastic part is in the upper tool of the still open Device a defined amount of plastic in the form of a Inserted plastic disc and then the device closed. Then the plastic disc is melted and the melted plastic by one in the top die arranged in the desired shape presses, the liquid plastic also being inserted into the Textile penetrates well and cools down the plastic connects with him intimately. Finally, the finished composite part removed from the device. For pressure sensitive materia lien, such as B. felt, on the back, for example. Fastening tion elements such as clips or the like are formed in this method on the visible side, due to the  high pressure and temperature when molding these parts, a clear, thermal and / or pressure-related change the visible side. Among pressure sensitive materials are Ma materials such as felt, laminating foils or the like understand that when applying pressure and / or temperature her Change appearance. However, this effect is because it is on the Visible side leaves markings, especially for related or uncovered components. Furthermore, it is Load the tool with the plastic plates, if it is done manually, very expensive, or it requires a high level of mechanization. Otherwise, the Tiles separately in a previous manufacturing step be put.

Furthermore, DE-OS 31 45 808 describes a method for Production of a composite body made of plastic and tex tilem tissue is known. The procedure uses a Preform made, the plastic melt the fabric presses against the wall of the associated hollow shape. The rest The heat of the preform is used in the hollow to connect the inlaid fabric with the preform. For the attachment of an opposite to the extension of the tissue Smaller plastic part, however, this method is not is suitable because, due to the large amount of heat Plastic melt and the pressure exerted on the fabric, the Badge badly plastic part on the visible side of the fabric net.

Furthermore, a method is known from DE-OS 32 06 254, at a plastic part is molded onto a fabric. For this the tissue is inserted into an injection mold in a defined position, the injection mold closed and the plastic part is splashes. With this procedure, too, the art stands out from the fabric part on the visible side of the fabric.

The object of the invention is the underlying method Ren to improve and a device for through to further develop the management of the process so that the Aesthetics of the visible side are preserved.

The object is achieved by the in claims 1 and 6 mentioned characteristics solved. In the invention, its technical teaching is not based a variety of plastic parts is limited, but also applies to a single plastic part, this is for the connection that of the plastic part with the workpiece on the workpiece exerted pressure only about 1 kg / cm² and is therefore around Factor of about 200-300 less than if an art part of the fabric is molded directly. Furthermore, the is led amount of heat, both in the underlying process as well as injection molding in the entire mass of the melted zenen plastic and stored on the workpiece is transferable due to the significantly lower ge melted plastic mass, many times less. Out  For these reasons, the aesthetics on the visible side change of the work made of a pressure sensitive material no piece.

Furthermore, since the plastic parts in the injection mold are the same injection molded from a granulate in a defined position, then remain in the injection mold and therein until after Ver bind, the procedure points from the beginning of the Granulate processing for later molding the plastic parts less process until they are connected to the workpiece steps on.

Furthermore, it is advantageous in this process that the Position of several plastic parts to each other almost no tolerances exhibit.

The invention is based on a Darge in the drawings presented embodiment explained below. Here shows

Fig. 1 a plastic part in the mold with material supernatant during injection molding,

Fig. 2 shows the plastic part according to Fig. 1 with the sheet material arranged in a position-defined manner at the bottom

Fig. 3 the plastic part intimately connected to the web material in the tool according to Fig. 2 and

Fig. 4 shows an inventive tool for performing the method according to the invention.

In Fig. 1, the injection molding of a plastic part 17 with material overhang 18 is shown. The injection molding is performed in a an upper (3) and a lower tool 4 having tools. In the largely simulated an injection mold and provided with a material supply 14 for the liquefied plastic upper tool 3 , the injection mold of the plastic part 17 is arranged. With several be mounted plastic parts 17 whose mutual relative position of those relative positions, the to be molded and have later with the manufactured from textile sheet material workpiece 19 to be connected to the plastic parts 17. Compliant The molding surfaces of the injection mold of the upper tool 3 form common sam with the befind union in a first, upper closing position lower tool 4, the entire injection mold of each plastic part 17, the mold parting plane with plastic parts 17 without material supernatant 18 between the upper (3) and the Lower tool 4 is arranged. Thus, the mold division level corresponds to the later transition plane between the workpiece 19 and the respective plastic part 17 . If the plastic part 17 has a material rial overhang 18 for later hot gluing, it is useful to arrange a piston 16 in the lower tool 4 , which is retracted in the first closed position of the lower tool 4 by the amount of the axial extension of the material overhang 18 downwards . For injection molding of the plastic part 17 , the lower tool 4 is then sealingly applied to the upper tool 3 with the piston 16 withdrawn, and the liquid plastic is introduced into the injection mold through an injection nozzle (not shown). After an at least partial solidification of the plastic, the lower tool 4 and the upper tool 3 are separated from one another again, the plastic part 17 remaining completely in the upper tool 3 up to its plane of molding. The cooling or cooling of the plastic part 17 takes place the faster the better the heat conduction of the material surrounding the injection mold. It is advantageous here to additionally cool the upper tool 3 and possibly also the lower tool 4 with a cooling device, for example cooling coils arranged in the upper tool 3 and through which water flows.

In FIG. 2, the second step of the process is illustrated. For this purpose, the workpiece 19, for example made of textile web material or a foamed sheet, was previously inserted in a defined position in the opened tool, the piston 16 withdrawn to form the excess material 18 being returned to its starting position, in which the piston crown with the surface of the lower tool 4 is aligned. In addition to the position-defined insertion, it is advantageous to additionally hold the workpiece 19 , which can be done, for example, by a frame 15 placed in the outer region. Is in plastic parts 17 without material supernatant 18 the lower tool 4 is transferred to closing in a second closed position, the ge genüber the first closed position, measured from the lower tool-facing side of the plastic part 17, offset by the thickness of the workpiece 19 downward. In the second closed position, the workpiece 19 completely fills the space between the upper ( 3 ) and lower tool 4 . In this case, an adhesive is applied, for example, before the lower tool 4 is transferred to its second, lower closed position on the workpiece 19 or on the plastic part 17 in the area of its later intimate connection. When plastic parts 17 with material supernatant 18 the lower tool 4 is first applied and the nearest surface of the material it supernatant 18 slowly transferred into the second closed position under a melting of the plastic of Ma terialüberstandes 18th

In Fig. 3 the connection of the plastic part 17 to the workpiece 19 is shown. As can be seen in the gate, the adhesive connected to the plastic part 17 has penetrated into the workpiece 19 , as a result of which it intimately connects the two parts to one another. In the case of plastic parts 17 with material protrusion 18 , this is liquefied, for example by friction, after the workpiece 19 has been placed on it, and is used as a hot glue which penetrates into the workpiece 19 and, like the separate adhesive before, binds intimately to the latter and the plastic part 17 , just as before . The material protrusion 18 thereby replaces the additional application of adhesive.

After the connection has finally been made, the tool is opened again and the plastic part (s) 17 which has been arranged in the upper tool 3 since molding injection molding has been removed. After removal from the mold, the finished workpiece 19 provided with the plastic part (s) 17 is removed.

In Fig. 4 shows a device for performing the method, wherein the left half of the figure, the apparatus for injection molding, and the right half of the figure shows the device during the friction welding. The inside of the device has the tool consisting mainly of lower tool 4 and upper tool 3 and is described starting from the tool. In the upper tool 3 , the injection molds of the plastic parts 17 are arranged, an entire injection mold of a plastic part 17 being formed by the shaping surfaces together with the lower tool 4 . The injection molds are connected via a material feed 14 to an injection unit 1 , in which a plastic granulate is liquefied and pressurized. The injection unit 1 and thus also the upper tool 3 are arranged on a head plate 2 , which is rigidly arranged on the other hand at the upper end of vertically aligned column guides 8 . In the lower tool 4 , recesses are arranged on the areas opposite the injection molds, which can be filled by a piston 16 which is also arranged in the lower tool 4 and is movable within a guide aligned parallel to the opening movement from the upper tool 3 to the lower tool 4 . The pneumatically or hydraulically actuated pistons 16 via a pressure line here have two different stroke positions, of which in one stroke position the piston head is aligned with the upper tool 3 side of the lower tool 4 . The lower tool 4 is connected to an oscillating plate 5 which is axially arranged below and provided with springs 6 to form a vibrating table which is surrounded on its outer circumference by electromagnets 12 . The electromagnets 12 drive the vibration system. The vibrating plate 5 is also connected via the springs 6 of the vibrating system to a pressure plate 7 , which in turn is in engagement with first hydraulic cylinders 8 , which are attached to an axially below arranged and vertically movable table 13 . The vertically movable table 13 and thus the lower tool 4 is guided by the laterally arranged columns guides 8, the vertical movement is effected by a second Hydraulikzylin the 10th This second hydraulic cylinder 10 can also be used to approach the two closed positions, which differ by the material thickness of the workpiece 19 . To secure the first closed position and thus the necessary in this position closing pressure 2 spacer sleeves 11 are arranged at the upper ends of the column guide 8 between the vertically movable table 13 and the head plate, which limit the vertical movement of the table. The first hydraulic lik cylinder 8 have the task of pressing the lower tool 4 placed with the workpiece 19 during friction welding over the pressure plate 7 arranged vertically movable within the table 13 against the plastic part 17 .

Claims (7)

1. Method for attaching plastic parts in a position-defined manner to a workpiece formed from a lobed sheet material, in which a melted plastic is formed into a plastic part in a tool, the workpiece is inserted in a defined position in the tool and the plastic parts are intimately connected to the work piece in the closed tool are characterized by

• - That first the plastic parts ( 17 ) for themselves in the closed mold are formed by the injection molding process, the lower tool ( 4 ) sealingly in the area of the mold parting level to the injection molds of the plastic parts ( 17 ),
• - That after the injection molding and an at least partial cooling of the plastic parts ( 17 ), the workpiece ( 19 ) is inserted in a defined position in the mold, the molded plastic parts ( 17 ) remaining on one side up to the mold parting plane in the injection mold,
• - That the lower tool ( 4 ) for closing in a defined, compared to the lower side of the plastic part ( 17 ) in relation to the upper tool ( 3 ) is approximately offset by the wall thickness of the web material down second closed position is created and
• - That the workpiece ( 19 ) is connected within the closed tool with the plastic parts ( 17 ).

2. The method according to claim 1, characterized in that the connection of the plastic parts ( 17 ) to the workpiece ( 19 ) by a separate, brought between the plastic parts ( 19 ) and the workpiece ( 19 ) in the area of the subsequent connection, with the respective plastic part ( 17 ) and with the workpiece ( 19 ) connecting adhesive. 3. The method according to claim 1, characterized in
that during the injection molding of the plastic part ( 17 ) in the area of the subsequent connection, a material protrusion ( 18 ) is molded onto the plastic part ( 17 ) and
that to connect the plastic part ( 17 ) to the workpiece ( 19 ), the plastic of the excess material ( 18 ) is liquefied as an adhesive. 4. The method according to claim 3, characterized in that the plastic of the material overhang ( 18 ) liquefied by friction welding and the connection is performed as a hot glue. 5.Device for the position-defined attachment of plastic parts to a piece formed from a lobed sheet material, in particular textiles, with a plastic mold made of melted plastic in molds, and also with a position-defining workpiece taking the lower mold, the respective molds being removed speaking of the position provided on the workpiece are arranged within the upper tool for carrying out a method according to claim 1, characterized in
that the upper tool ( 3 ) with a material supply ( 14 ) has injection molds, the shaping surfaces of which are formed together with the lower tool ( 4 ), the mold parting plane being arranged on the plane which will later become the transition plane from the workpiece ( 19 ) the plastic parts ( 17 ) and
that the lower tool ( 4 ) in relation to the upper tool ( 3 ) has two different closing positions, which differ approximately by the material thickness of the web material. 6. The device according to claim 5, characterized in that
that the lower tool ( 4 ) on the areas opposite the injection molds has depressions which can be filled by a piston ( 16 ) which is movably arranged in a lower tool ( 4 ) within a guide which is aligned parallel to the opening movement from the upper tool ( 3 ) to the lower tool ( 4 ) . 7. The device according to claim 5, characterized in that the lower tool ( 4 ) is designed as a vibrating table of a vibration welding system.