DE10031523A1 - Producing folded and adhered connection in automobile manufacture, heats surfaces to be adhered, coats with hot melt adhesive powder and closes fold continuously - Google Patents

Abstract

At least one of the opposite surfaces (1, 2) of the workpieces, is heated over a defined area to a temperature above the melting point of an adhesive (9). This surface is then sprayed with powdered adhesive. This only sticks to the hot surface, by melting-on. The open fold (6) is then closed, pressing opposite surfaces together. As a result of cooling the surfaces, the adhesive cools below its melting point, forming the bond. An Independent claim is included for corresponding equipment. A series of roller pairs (3, 4) through which the workpieces (1, 2) are passed, continuously closes the fold. Rollers inclinations are adjusted to progressively close the fold. A heat source (7) and powder spraying nozzle (8) are also included. Preferred features: Non-adherent thermoplastic powder adhesive is sucked away, before closing the fold. A thermoset powder is alternatively used. Bonding of the workpieces takes place progressively during a single, continuous working operation.

Description

The invention relates to a method and an apparatus for producing a folding Adhesive connection between workpieces with approximately the same in the connection area flat and / or curved structure, one of the workpieces to achieve the Folded connection is preformed such that an open fold is formed in which at least one further workpiece can be introduced and the workpieces both by gluing as well as by closing the fold on their contact surfaces be firmly connected.

Fold-glue connections between workpieces, preferably flat workpieces, have long been known, especially from the automotive industry.

DE 197 05 864 A1, for example, provides a tight connection between two Corrosion-protected sheets are proposed, being between two sheets, in A ride is formed on the inside of the component and a sealing material in this groove, which can be an adhesive, is provided and possibly even before Join the connection of the sealing material to one of the sheet metal parts to be connected is applied.

More concrete information on the execution of the joining process is this disclosure not to be removed.

Furthermore, DE 42 24 423 A1 is a vehicle sheet metal part with a flange as well a device for producing the same in the form of a so-called flanging die can be seen, which in turn the special shape of the flared seam to be created realized. Essentially, the conveyor flange encompasses the fold spaced edge of a component, the fold having such a strong curvature has that the mutually facing sheet metal part inner surfaces near the fold at least almost touch while one of the flanged flange is spaced from the fold Has thickness of the component edge adapted level. Furthermore, that should Component be glued to the sheet metal part at least in sections.  

How the adhesive connection is actually realized is not disclosed.

From practice it is known per se, one that is semi-fluid in nature (pasty) adhesive by means of devices for application in the form of nozzles, for example disclosed in DE 39 12 782 A1, caterpillar or ring-shaped on the Apply workpiece.

Attempts are being made to meter the adhesive in such a way that it does not come from a if applicable, provided and to be closed glue point, which can be a fold, emerges, however, shows in practice that due to existing Tolerance differences between the workpieces to be connected Adhesive leakage is recorded regularly.

Another disadvantage is that this adhesive ultimately as Hazardous waste must be disposed of.

This is where the invention described below comes into play.

The object of the invention is a method and an apparatus for producing a Fold-glue connection between workpieces with approximately in the connection area same flat and / or curved structure to indicate which in improvement of the State of the art reduce the use of adhesive to the required extent, consequently avoid or significantly minimize the generation of hazardous waste and Possibility to open up the workpieces in a single continuous Joining processes together, which ultimately results in material and Cost savings have been recorded.

According to the invention, the object is achieved by means of a method for producing a folding Adhesive connection between workpieces with approximately the same in the connection area flat and / or curved structure solved, wherein in connection with the features in Preamble of claim 1 at least one of the two each facing each other standing surfaces of the workpieces in a possibly defined Surface section to a temperature above the melting point of an adhesive is heated, then the heated surfaces with the adhesive in the form of Powders are sprayed in such a way that they only result on the heated surfaces Adheres to melting and finally the open fold is closed in such a way that the two opposing surfaces of the workpieces collide and the adhesive due to cooling of the heated surfaces  below the melting temperature of the same an adhesive bond between the themselves based areas realized.

In one embodiment of the invention, non-adherent powder of the adhesive is used the closing of the fold sucked out of the same.

It is also proposed to use a thermoplastic or an adhesive thermosetting plastic and the connection of the workpieces to each other to be carried out continuously in one go.

The device for producing a fold-adhesive connection between workpieces with in the connection area approximately the same flat and / or curved structure is particularly characterized by the fact that they consist of two or more in series there are pairs of rollers arranged one behind the other, between which the to connecting workpieces are progressively guided, one roller of each pair of rollers each acts as a backup roller and the second roller as a bending roller and all Bending rolls have such an attitude to the associated backup roll that in Seen in the direction of movement of the workpieces, the fold can be closed continuously is, the device at least one heat source for heating at least one of the two opposing surfaces of the workpieces is assigned in a possibly defined surface section and this Heat source in turn at least one spray nozzle for a powdery adhesive is subordinate.

In an inventive further development of the device, it is proposed that the support roller and / or bending roller in each case a progressive movement of the to be connected Realizing workpieces themselves or the workpieces to be connected in their progressive movement are arranged freely rotating.

Furthermore, in the context of the invention, the adhesive is a powder in the initial state a thermoplastic or thermoset plastic.

Another expedient measure provides that the device has at least one Suction device for powdery powder not adhering to heated surfaces Adhesive is assigned.  

The advantages achieved with the invention are seen in particular in that after the inventive method using a single inventive Device for producing a fold-adhesive connection between workpieces the composite can be produced continuously in one operation.

Furthermore, an optimal use of adhesives can be recorded in such a way that subsequent expenses for cleaning the composite workpiece and / or Disposal of hazardous waste in the form of leaked and cured adhesive can be avoided or significantly minimized.

Furthermore, a visually appealing joining seam is produced using this method. Furthermore, the device performing the above method is advantageous in FIGS Manufacturing process, for example in the automotive industry, can be integrated because of itself known high manual effort is minimized by increased mechanization.

Further details of the invention emerge from the explanation below an embodiment shown schematically in the drawings.

Show it:

Fig. 1 shows a detail, shown in perspective of the inventive process executing device,

Fig. 2 shows the view A of FIG. 1.

Figs. 1 shows in perspective a detail of a device for manufacturing a folding-glueing connection between flat workpieces 1; 2 , two pairs of rollers 3 ; 4 , between which the workpieces 1 and 2 to be connected are progressively guided in the rolling direction. The workpieces 1 and 2 to be connected have approximately the same flat and / or curved structure in their connection area and can be made of metal, for example steel or aluminum sheet, as well as of other materials, such as, for. B. plastic plates exist.

Any suitable number of further roller pairs 5 ( FIG. 2) can be arranged both in front of the roller pair 3 and behind the roller pair 4 .

In the present exemplary embodiment, the workpiece 1 contains a preformed open fold 6 in which the workpiece 2 is introduced.

One roller of each pair of rollers 3 ; 4 ; 5 acts as a backup roller 3 a; 4 a; 5 a the second as a bending roller 3 b; 4 b; 5 b.

All bending rollers 3 b; 4 b; 5 b have such an employment to the associated backup roller 3 a; 4 a; 5 a that in the direction of movement of the workpieces 1 and 2 to be connected , ie, seen in the rolling direction, a continuous closing of the fold 6 formed by the workpiece 1 can be realized.

Seen in the rolling direction, preferably between two pairs of rolls 3 ; 4 , at least one heat source 7 is arranged, which in turn is suitable for at least one of the two mutually opposing surfaces of the workpieces 1 ; 2 to heat. Known gas or electric heat radiators, but also laser devices, are considered suitable. Likewise suitable for metal workpieces 1 ; 2 also heat sources 7 , which utilize known electromagnetic induction.

According to the present exemplary embodiment, two heat sources 7 were provided, which in turn can heat at least the workpiece 2 on both sides in a defined area, ie in the area of the future joint connection.

It goes without saying for the person skilled in the art that the surfaces can also be heated by using a single heat source 7 , in particular if the workpiece 2 consists of a metal with good thermal conductivity, for example aluminum.

The heat source 7 is in turn followed by at least one spray nozzle 8 for a powdery adhesive 9 and at least one suction device 10 for powdery adhesive 9 , which does not adhere to the heated surfaces of the workpieces 1 and / or 2 , but it must be ensured that with the spray nozzle 8, the heated surfaces are reached, which are required to realize the bond by gluing.

In the present case, a spray nozzle 8 and a suction device 10 were arranged on both sides of the workpiece 2, each heat source 7 .

Both thermoplastic plastics, for example polypropylene or polyethylene, and thermosetting plastics, for example epoxy resins, have proven to be suitable adhesives 9 .

Furthermore, it is indicated to provide guide elements 11 in the nearer area of the spray nozzle 8, at least for the workpiece 2 introduced into the fold 6 of the workpiece 1 , in order to guide the workpiece 2 at a distance from the workpiece 1 such that there is a gap between the surfaces to be connected Workpieces 1 and 2 is formed, which in turn ensures problem-free spraying of powdered adhesive 9 into the gap formed in each case and accordingly onto the heated surfaces, and suction of non-adhesive 9 .

Known fixedly arranged guide rollers or guide rollers are proposed as guide elements 11 .

The function of the invention is described in more detail below.

., Corresponding to FIGS 1 and 2, a preformed and a fold 6 forming progressively in a single pass between the pairs of rollers 3; 4 ; 5 led.

This movement is realized in the preferred embodiment such that the support rollers 3 a; 4 a; 5 a and / or bending rolls 3 b; 4 b; 5 b are themselves driven and, as a result of the static friction on the workpiece 1, transport the same together with the workpiece 2 in the rolling direction

It goes without saying that, on the one hand, support rollers 3 a; 4 a; 5 a and bending rollers 3 b; 4 b; 5 b must be designed to be driven, but also only one of them of each pair of rollers 3 ; 4 is driven and the other rotates freely, but on the other hand also all support rollers 3 a; 4 a; 5 a and bending rollers 3 b; 4 b; 5 b can be freely rotating and the workpieces 1 and 2 in a manner not shown by the roller pairs 3 ; 4 are pushed or pulled through to ensure the necessary shaping of the fold 6 .

As a result of the continuously increasing angle of attack a of the bending rollers 3 b; 4 b; 5 b to the associated backup roller 3 a; 4 a; 5 a there is a closing of the fold 6 .

Seen in the rolling direction between the two pairs of rollers 3 ; 4 , a heat source 7 is arranged on both sides of the workpiece 2 , which heat at least the immediate joining area of the workpieces 1 and 2 to such a temperature that an adhesive 9 , consisting of thermoelastic or thermosetting plastic powder, adheres to them as a result of melting.

The required temperature range is preferably in the range between 50 and 250 ° C.

In practice, it has proven sufficient if only the two surfaces of the workpiece 2 are heated.

As a result, the heated workpieces 1 and 2 pass through the spray area of the spray nozzles 8 by means of which the powdered adhesive 9 is sprayed into the gaps between the workpieces 1 and 2 formed as a result of the positive guidance (guide means 11 ) of the workpiece 2 .

The powdery adhesive 9 melts during contact with the heated surfaces of the workpieces 1 and / or 2 and consequently adheres to them.

Powdery adhesive 9 that does not adhere is sucked off by means of the following suction devices 10 .

Finally, the workpieces 1 and 2 pass through the last pair of rollers 5 and are firmly joined to realize a joint.

As soon as the temperature of the connecting surfaces of the workpieces 1 and 2 has fallen below the melting temperature of the adhesive 9 , the adhesive connection is also completed in addition to the fold connection.

In conclusion, it can be stated that it may be appropriate not only to insert a workpiece 2 into the fold 6 of the workpiece 1 , but rather to carry out a fold-adhesive connection from a workpiece 1 and a plurality of workpieces 2 in accordance with the configuration of the fold 6 .

This embodiment, which differs essentially from the one described above only in that a correspondingly adapted number of heat sources 7 , spray nozzles 9 , suction devices 10 and guide elements 11 is to be arranged, is expressly covered by the invention.

Claims (9)

1. A method for producing a fold-adhesive connection between workpieces with a planar and / or curved structure which is approximately the same in the connection region, one of the workpieces being pre-shaped in order to achieve the fold connection such that an open fold is formed in which at least one further workpiece can be introduced and wherein the workpieces are firmly connected to one another at their contact surfaces both by gluing and by closing the fold, characterized in that
at least one of the two opposing surfaces of the workpieces ( 1 ; 2 ) is heated to a temperature above the melting point of an adhesive ( 9 ) in an optionally defined surface section, then the heated surfaces with the adhesive ( 9 ) in the form of powder in this way be sprayed that this only adheres to the heated surfaces as a result of melting and
finally the open fold ( 6 ) is closed in such a way that the two opposing surfaces of the workpieces ( 1 ; 2 ) are pressed together and the adhesive ( 9 ), as the heated surfaces cool below the melting temperature, forms an adhesive bond between the contacting surfaces realized. 2. The method according to claim 1, characterized in that non-adhering powder of the adhesive ( 9 ) is sucked out of the same before closing the fold ( 6 ). 3. The method according to any one of claims 1 and 2, characterized in that a thermoplastic is used as the adhesive ( 9 ). 4. The method according to any one of claims 1 to 3, characterized in that a duromer plastic is used as the adhesive ( 9 ). 5. The method according to any one of claims 1 to 4, characterized in that the connection of the workpieces ( 1 ; 2 ) to each other takes place continuously progressively in one operation. 6. Device for producing a fold-adhesive connection between workpieces with a planar and / or curved structure that is approximately the same in the connection area, one of the workpieces being preformed in order to achieve the fold connection in such a way that an open fold is formed in which at least one further workpiece can be introduced and wherein the workpieces are firmly connected to one another at their contact surfaces both by gluing and by closing the fold, characterized in that the device for carrying out the fold connection consists of two or more pairs of rollers ( 3 ; 4 ; 5 ) arranged in series , between which the workpieces to be connected ( 1 ; 2 ) are guided, one roller of each pair of rollers ( 3 ; 4 ; 5 ) each as a backup roller ( 3 a; 4 a; 5 a) and the second roller as a bending roller ( 3 b; 4 b; 5 b) acts and all bending rollers ( 3 b; 4 b; 5 b) such an employment to the associated Backup roller ( 3 a; 4 a; 5 a) have that in the direction of movement of the workpieces ( 1 ; 2 ) a constant closing of the fold ( 6 ) can be realized, furthermore the device has at least one heat source ( 7 ) for heating at least one of the two opposing surfaces of the workpieces ( 1 ; 2 ) is assigned in an optionally defined surface section and this heat source ( 7 ) is in turn followed by at least one spray nozzle ( 8 ) for a powdery adhesive ( 9 ). 7. The device according to claim 6, characterized in that the supporting roller ( 3 a; 4 a; 5 a) and / or bending roller ( 3 b; 4 b; 5 b) each realize a progressive movement of the workpieces to be connected ( 1 ; 2 ) are themselves driven or the workpieces ( 1 ; 2 ) to be connected are arranged in a progressively freely rotating manner in their progressing movement. 8. The device according to claim 6, characterized in that the adhesive ( 9 ) is a powder of a thermoplastic or thermosetting plastic in the initial state. 9. The device according to claim 6, characterized in that the device is assigned at least one suction device ( 11 ) for powdery adhesive ( 9 ) not adhering to heated surfaces of the workpieces ( 1 ) and / or ( 2 ).