EP0696956A1

EP0696956A1 - Process for manufacturing a profile moulding

Info

Publication number: EP0696956A1
Application number: EP94911929A
Authority: EP
Inventors: Hans-Volker Buchholz; Alistair Hill
Original assignee: Meteor Gummiwerke KH Badje GmbH and Co
Current assignee: Meteor Gummiwerke KH Badje GmbH and Co
Priority date: 1993-04-30
Filing date: 1994-03-19
Publication date: 1996-02-21
Also published as: GB9510680D0; GB2287429A9; GB2287429B; GB2287429A8; CA2157277C; DE4314192C2; WO1994025246A1; DE4314192A1; US5736215A; GB2287429A; CA2157277A1

Abstract

A composite section (43) consists of a fastening rod (33) made of a thermoplastic material and of section rods (30, 31) made of elastomers, i.e. a section rod (30) made of sponge rubber and a section rod (31) made of soft rubber. All rods (30, 31, 33) are secured to each other by co-extrusion and co-vulcanisation. The plastic fastening rod (33) takes over the function of the usual metallic reinforcements of state-of-the-art composite sections (43). The composite section (43) may thus be three-dimensionally shaped, in that it is heated up to the melting temperature of the fastening rod (33), which is then given the desired shape in a shaping tool and cooled in said shape until the fastening rod (33) has regained its non-plastic state. A dimensionally stable profile moulding is thus obtained.

Description

1 B E S C H R E I B U N G

Process for producing a shaped profile part

The invention relates to a method according to the preamble of claim 1.

05 In a known method of this type, the so-called "stretch bending", the fastening strand consists of a metallic reinforcement. The finished composite profile is bent in a labor-intensive manner in special tools to the shape in which it is finally installed as a profile molded part in a motor vehicle. Due to the construction tolerances, there is regularly a complex readjustment of the stretch-bent composite profile during assembly.

From DE 37 37 891 AI the co-vulcanization of 15 thermoplastics and elastomers is known per se. Working in the two-stage extrusion process is mentioned, which is time-consuming and labor-intensive.

From DE 42 19 344 AI it is known per se by a sandwich injection molding process in a mold 4

20 to 7 produce a molded part 1, which has a core 3 made of a resin mixture, mainly made of PP (p.5, lines 50 and 51), and a skin layer 2 made of a resin (p.5, line 55), namely one styrene-based thermoplastic elastomer consisting mainly of SEBS (p.5,

25 Z.49 and 50). From DE 39 34 091 AI it is known per se to create composite bodies in two stages which consist of an endless fiber-reinforced thermoplastic material and rubber and which can be firmly connected to one another by vulcanization without the use of adhesion promoters, primers or adhesives . As a rule, in the first stage the thermoplastic material is bound to a fibrous reinforcement, eg fabric, UD tapes, etc.

From DE 38 35 211 AI it is known per se, a sealing strip 1 from a U-shaped clamping strip 4 made of hard rubber, a complete casing 5 of the clamping strip 4 and with lips 9, 10 made of soft rubber and a sealing tube 3 made of foam rubber to extrude a common spray head 21. The composite profile 1 then passes through a heating station 22 and a hot air section 23 that completes the vulcanization.

From DE-A-2 330 605 it is known per se to heat a thermoplastic PA synthetic resin material so that at least its surface softens and then to bring it into contact with a rubber composition, whereupon the softened surface comes into contact with the Rubber composition is allowed to cool. The rubber composition can be vulcanized.

From the DE book: "Entry into plastics chemistry", 3, edition, by B. Gnauck and P. Fründt, Carl Hanser Verlag, Munich / Vienna, 1991, p.31, the thermoforming of thermoplastic materials is known per se . Thermoplastics can be plastically formed by the sufficient supply of heat and after cooling to normal temperature firm and resilient again.

The invention has for its object to improve and simplify the manufacture and assembly of shaped profile parts.

This object is solved by the features of claim 1. Of particular interest are profile molded parts according to the invention for bodywork applications in which the original profiles have to be three-dimensionally deformed into profile molded parts. The bodybuilder is constantly striving to reduce the drag coefficient and noise level in the motor vehicle. The result is that the bodies are rounded more and more and the ornaments and seals which are attached to the outside of the body have to follow this shape. To do this, it is also necessary to deform composite profiles in all three coordinates. The method according to claim 1 makes it possible to completely eliminate metal as a material for the at least one fastening strand. The composite profiles produced according to the invention are cut to length and are shaped only by heating, shaping in a molding tool and cooling in the thus shaped state to give shaped profiles of extraordinarily high accuracy of fit. The assembly of the profiled parts produced in this way is made considerably easier because the profiled parts already have an optimal fit to the receiving track on the body. Another advantage over the easier assembly is that such optimally pre-shaped molded parts ensure an equally optimal sealing effect in the installed position when it comes to sealing profiles. However, molded profile parts produced according to the invention can, for example, also serve as rain strips. In all profile molded parts according to the invention, the fastening strand can be of the type of the thermoplastic and in its cross section so that the necessary strength and shape stability result later for the entire shaped profile part. The shape of the profile molding obtained after cooling is to a certain extent "frozen" and does not change until the profile molding is installed. The production of the composite profile by coextrusion and co-vulcanization results in manufacturing advantages. However, production can also be carried out by pressing or injection molding.

According to claim 2, the extrusion of the fastening strand can take place at temperatures> 220 ° C. The shaped fastening strand is cooled and calibrated to a coextrusion temperature in front of the multi-component spray head. Thermoplastic elastomers

(TPE) are co-extruded at temperatures of 150 to 190 C together with the fastening strand, cooled to room temperature and calibrated. In the case of the elastomers, the extrusion usually takes place at from 80 to 120 ° C, the temperature supply for the crosslinking in the vulcanization section, e.g. in a salt bath or in a fluid bed.

According to claim 3, the desired firm bond between the components can be achieved even in difficult cases.

In each of claims 4 to 11, exemplary embodiments of profile molded parts produced according to the invention are characterized.

Further features and advantages of the invention result from the following description of exemplary embodiments with reference to the drawings. It shows: 1 is a composite profile before forming,

FIG. 2 three interacting molded profile parts produced from the composite profile according to FIG. 1, FIG.

3 shows the cross section along line III-III in FIG. 1 in an enlarged view,

4 shows a cross section through another, assembled profile molding,

Fig. 5 shows a cross section through another assembled molded part and

Fig. 6 shows a cross section through yet another shaped profile part.

1, a composite profile 43 has been produced continuously from several strands by coextrusion and co-vulcanization. In Fig. 3 only a large circumferential area of the composite profile 43 covering profile strand 30 made of foam rubber can be seen. The remaining strands will be described in detail in connection with FIG. 3.

For further processing, 43 pieces of suitable length are separated from the composite profile and heated in a molding tool, not shown, if necessary only locally, until thermoplastic strands of the composite profile 43 have transitioned into the plastic state. The composite profile piece is then brought into the desired shape in the molding tool and then cooled until the plasticized strands of the composite profile 43 have reached their non-plastic state again. Thereby profile molded parts 1, 2 and 3 according to FIG. 2, which are used, for example, as sealing profiles in a convertible top. The front ends of the profiled parts 1 to 3 can, if required, be closed in a manner known per se by caps or other prefabricated closures and, in the open state of the top, lie against one another in a sealed manner along separating joints 4 and 5. To simplify the illustration, the other components of the convertible top are omitted in FIG. 2.

In principle, the invention is not only suitable for creating two- or three-dimensionally deformed sealing profiles for the roof frame of folding tops or for hardtops. In particular, rain strips, water box seals under the hood of motor vehicles, window manhole profiles and roof frame seals on limousines can also be produced for the motor vehicle industry in a precisely fitting and dimensionally stable manner. In all cases, at least one fastening strand 33 and 55 made of a thermoplastic material takes over the function of the previous metallic fastening rail.

The heating of the composite profile to reduce the plastic state of its plasticizable components can e.g. done by radiant heaters, hot air blowers or high frequency.

The same parts are provided with the same reference numbers in all drawing figures.

3 shows a composite profile 43, in which the profile strand 30 consists of foam rubber and almost completely surrounds the composite profile 43. In the interior of the profile strand 30, a profile strand 31 is arranged, which also consists of a Elastomer, in this case made of soft rubber, and has a chemical bond with the profile strand 30 at the parting surfaces. Continuous cavities 44 and 45 are formed between the profile strands 30 and 31 to improve the elastic properties of the composite profile 43.

3 has a substantially T-shaped cross-sectional area and is partially embedded in the profile strands 30, 31, here too a sufficiently strong chemical bond at the interfaces due to the aforementioned coextrusion and co-vulcanization consists.

At its lower free end, the composite profile 43 in FIG. 3 has mounting openings 46 arranged at a distance from one another in the longitudinal direction, through which a fastening element can be guided and connected to a body part, not shown. A lip 48 of the profile strand 30 made of foam rubber covers the assembly openings 46. The composite profile 43 serves e.g. as a sealing profile for the front transverse section of the roof frame of a folding top or hard top for a convertible or also for a coupe.

Fig. 4 shows another composite profile 29, which is composed of four profile strands 30 to 33. The profile strands 30, 32 consist of foam rubber, the profile strand 30 being provided with a continuous cavity 34 in order to further improve its suspension properties.

The profile strand 31 is also provided with a continuous cavity 35 in order to achieve optimum suspension properties. The profile strand 31, like the profile strands 30, 32, is made of an elastomer. The following materials, for example, can be used as elastomers for the profile strands, for example 30 to 32, in all the figures:

Foam rubber with a hardness of 10 to 30 Shore-A or soft rubber with a hardness of 30 to 70 Shore-A, both e.g. made of

EPDM,

SBR,

CR, ECO,

Blending (blending) of EPDM with SBR with an EPDM weight fraction of 20 to 90%,

Blended EPDM with SBR and / or Polyoctenamer, or NBR.

The following can be used e.g. also the following thermoplastic elastomers (TPE):

TPE based on styrene ethylene butylene styrene (S-EB-S), TPE based on styrene butadiene styrene (SBS),

TPE based on styrene isoprene styrene (SIS),

TPE based on elastomer alloys as TP0 blends or TPO alloys, e.g. of networked. EPDM / propylene blend (EPDM / PP) or ethylene vinyl acetate / vinylidene chloride (EVA / PVDC) or

TPE based on thermoplastic polyurethanes (TPU).

The profile strands, for example 30 to 32, are each through an elastomer extruder was molded and then vulcanized together along the interfaces in contact. There is a chemical bond of sufficient strength between the profile strands.

The fastening strand 33, on the other hand, consists of a thermoplastic material in all figures. For this come e.g. following substances into consideration:

PPE polyphenylene ether, PP polypropylene,

PE (LDPE, low density PE),

PE (HDPE, high density PE),

PIB polyisobutylene,

PS polystyrene, PA polyamide,

PC polycarbonate,

PETP polyethylene terephthalate,

POM polyoxy ethylene, epoxy resins, phenol formaldehyde resins,

PES polyester,

PPO polyohenyl ether or

PVC polyvinyl chloride.

These plastics can be with or without reinforcement, e.g. through carbon or glass fibers.

The fastening strand 33 is produced by a plastic extruder with a subsequent calibration and cooling section and has been co-extruded in a multi-component spray head with the profile strands 30 to 32. Due to the subsequent co-vulcanization, a sufficiently stronger chemical is also between the strands 31 and 33 Verbund emerged.

The composite profile 29 obtained in this way according to FIG. 4 is held on the one hand by an anchoring groove 36 on a folded edge 37 of a motor vehicle body 38 and on the other hand is fastened to a body panel 40 by a self-tapping screw 39 penetrating the fastening strand 33. This results in a stable connection of the composite profile 29 with the body 38 using the simplest means. The composite profile 29 serves e.g. as a sealing profile for the side parts of the roof frame of a folding top or hardtops for a convertible or also for a coupe.

FIG. 5 shows a composite profile 41 which is constructed and constructed essentially in the same way as the composite profile 29 according to FIG. 4. The connection to the motor vehicle body 38 is also carried out in the same way as in FIG. 4. The difference compared to FIG 4 consists in that a layer of a coupling material 42 is arranged between the strands 31 and 33. The coupling material 42 has the task of improving the chemical bond between the elastomer of the profile strand 31 and the thermoplastic plastic of the fastening strand 33. The coupling material 42 comes e.g. following substances into consideration:

EPDM in the blend with PP, PE, PS, PIB, PES, as well as other polymers from the above-mentioned list of the materials of the fastening strand 33 in parts by weight <20%,

Blends EPDM - CR - SBR - polyoctenamer or EPDM compounds with resin additives (e.g. epoxy resins).

If the profile strand 33 consists of a TPE, comes a polypropylene primer may be considered as coupling material 42.

6 shows yet another composite profile 47, which is particularly suitable as a sealing profile for the front transverse section and the side parts of the roof frame of a folding top or hard top for a convertible or also for a coupe.

The composite profile 47 has the fastening strand 33 made of a thermoplastic material and essentially formed with a U-shaped cross-sectional area. The fastening strand 33 is provided with a plurality of mounting openings 46 which are arranged at a distance from one another in the longitudinal direction and are each formed to form a sheet metal screw 39 with play on all sides. Thus, during assembly in the longitudinal and transverse direction, the composite profile 47 can be moved within limits relative to the self-tapping screws 39 until the optimal position of the composite profile 47 is reached. Then the self-tapping screws 39 are tightened.

A longitudinal end of the fastening strand 33 is shaped as a first coupling element 49. A cover profile strand 50 is vulcanized onto the fastening strand 33 on its longitudinal side opposite the first coupling element 49. The cover profile strand 50 has an additional profile strand 51 made of foam rubber, which is vulcanized onto a base 52 and a leg 53 of the fastening strand 33 via the coupling material 42. Part of the cover profile strand 50 is also a further profile strand 54 made of soft rubber covering the fastening strand 33, which has one longitudinal end vulcanized onto the additional profile strand 51 and with its other longitudinal end onto a coupling profile strand 55. is. The coupling profile strand 55 consists of a thermoplastic and has a second coupling element 57 which forms a snap closure 56 with the first coupling element 49.

A sealing profile strand 58 made of foam rubber is vulcanized onto the side of the fastening strand 33 opposite the additional profile strand 51 via the coupling material 42.

In FIG. 6, the body panel 40 to which the composite profile 47 is to be mounted is indicated by dash-dotted lines at the top. The serrated parts of the profile strands 51, 58 are pressed tightly against the body panel 40 and deformed accordingly. Up to the aforementioned tightening of the self-tapping screws 39, the snap lock 56 is released and the further profile strand 54 is folded down out of the way of the screwdriver. After the sheet metal screws 39 have been tightened, the further profile strand 54 with the coupling profile strand 55 is folded upward and the snap lock 56 is closed. This creates a cavity 59 into which a pane 60 of the motor vehicle can deform the further profile strand 54 when the convertible top is put on, as is indicated by dash-dotted lines in FIG. 6.

6, the major part of the outer surface of the additional profile strand 51 and of the further profile strand 54 are covered with an excessively thick, in reality wafer-thin sliding layer 61. The sliding layer 61 reduces the sliding friction between the further profile strand 61 and the disk 60.

Claims

PATENT CLAIMS

1. Method for producing a shaped profile part (1 to 3),

in which at least one profile strand (30 to 32) made of an elastomer is connected to at least one fastening strand (33; 55) and the composite profile (29; 41; 43; 47) thus obtained is brought into the desired shape,

characterized by the following steps:

a) the at least one fastening strand (33; 55) is produced from a thermoplastic,

b) the at least one fastening strand (33; 55) and the at least one profile strand (30 to 32) are co-extruded to form the composite profile (29; 41; 43; 47) and chemically bound to one another by co-vulcanization,

c) the composite profile (29; 41; 43; 47) is continuously produced and cut to length,

d) the cut composite profile (29; 41; 43; 47), depending on the location of a desired change in shape, is wholly or partially heated to the plastic state of its plasticizable components, and e) the composite profile (29; 41; 43; 7) pretreated according to step d) is brought into the desired shape in a molding tool and then cooled again to the non-plastic state of the plasticized components while maintaining the desired shape.

Method according to Claim 1, characterized in that the at least one fastening strand (33; 55) is extruded and calibrated before the coextrusion and is cooled to a temperature which is compatible with the elastomers of the at least one profile strand (30 to 32) for coextrusion.

3. The method according to claim 1 or 2, characterized gekenn¬ characterized in that at least one chemical compound promoting coupling material (42) also takes part in the coextrusion.

4. Profile molding, produced according to one of claims 1 to 3,

characterized in that a fastening strand (33) made of a thermoplastic material can be fixed to a body panel (40), and in that a profiled strand (31) made of soft rubber is vulcanized onto the fastening strand (33).

5. Profile molding according to claim 4, characterized in that at least one additional profile strand (30; 32) made of foam rubber is vulcanized onto the profile strand (31), and that such an additional profile strand (30) with a body area (cf. 37) can be coupled (cf. 36).

6. Profile molding, produced according to one of claims 1 to 3,

characterized in that a fastening strand (33) made of a thermoplastic material is essentially T-shaped,

that a profile strand (31) made of soft rubber is vulcanized onto a first part of the circumference of the fastening strand (33),

and that an additional profile strand (30) made of foam rubber is vulcanized onto a second part of the circumference of the fastening strand (33) and onto the profile strand (31).

7. Profile molding according to claim 6, characterized gekennzeich¬ net that the additional profile strand (30) surrounds substantially the entire rest of the composite profile (43) and on a longitudinal edge with a lip (48) via mounting openings (46) for receiving Fastening elements extends, the assembly openings (46) being located in the fastening strand (33) and in another longitudinal edge of the additional profiled strand (30).

8. Profile molding, produced according to one of claims 1 to 3,

characterized in that a fastening strand (33) made of a thermoplastic material is essentially U-shaped and has mounting openings (46) in its base (52) for receiving fastening elements (cf. 39), that a longitudinal edge of the fastening strand (33) is shaped as a first coupling element (49),

that a cover profile strand (50) is vulcanized onto the fastening strand (33) on its longitudinal side opposite the first coupling element (49),

and that a free longitudinal edge of the cover profile strand (50) is provided with a second coupling element (57) forming a snap lock (56) with the first coupling element (49).

9. Profile molding according to claim 8, characterized gekennzeich¬ net that the cover profile strand (50) has a further profile strand (54) made of soft rubber, with which the fastening strand (33) can be covered.

10. Profile molding according to claim 9, characterized in that a longitudinal edge of the further profile strand

(54) is vulcanized onto an additional profile strand (51) made of foam rubber, which in turn is vulcanized onto the fastening strand (33).

11. Profile molding according to one of claims 8 to 10, characterized in that the second coupling element (57) is formed in a coupling profile strand (55) from a thermoplastic material,

and that the coupling profile strand (55) is vulcanized onto the cover profile strand (50), which is otherwise made of elastomers.