Abstract:
A method and device in which at least part of a mold is moved periodically relative to the stationary thin-walled plastic profile and the thin-walled plastic profile is held by at least one holding means or gripper, which comprises a core and an outer holding part, whilst the mold is moved along the thin-walled plastic profile, which is stationary relative to said mold. Plastic material objects, in particular plastic profiles, are produced predominantly in a strand, preferably using the pultrusion method. In this case, the plastic profile is pulled through a mold. As a result of the plastic profile being pulled through the mold by a take-off device, it is only possible to form plastic profiles which withstand the force or the pressing pressure of the take-off device. Consequently, only plastic profiles which comprise sufficient wall thicknesses have been producible up to now.

Description:
STATEMENT OF RELATED APPLICATIONS 
       [0001]    The application is the US National Phase of International Application No. PCT/EP2015/000014 having an International Filing Date of 7 Jan. 2015, which claims priority on German Patent Application No. 10 2014 001 082.1 having a filing date of 30 Jan. 2014. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Technical Field 
         [0003]    The invention relates to a method for producing a thin-walled plastic profile where a continuous reinforcement produced from strands, woven fabric and/or the like is guided through a mold comprising at least one mold core and is embedded in the plastics material in the mold as well as to a device for producing a thin-walled plastic profile having a mold, which comprises at least one mold core, in which a continuous reinforcement of the plastic profile ( 30 ) is embedded in liquid plastics material. 
         [0004]    2. Prior Art 
         [0005]    Plastics material objects, in particular plastic profiles, produced from plastics material and a continuous reinforcement produced from fibers, woven fabrics and/or knitted fabrics, which are embedded in the plastics material, are predominantly produced in a strand. This is usually carried out using the pultrusion method. The reinforcement is guided through a mold for this purpose and the reinforcement is embedded in the mold in liquid plastic which then hardens in the mold. 
         [0006]    The hardened plastic profile leaving the mold is pulled through the mold by a take-off device, which is arranged in front of the mold in the pultrusion direction, and at the same time is simultaneously conveyed away. As a result of the plastic profile being pulled through the mold by the take-off device, only plastic profiles which withstand the force or the pressing pressure of the take-off device are able to be formed in the case of known methods of the described type, in particular in the case of known pultrusion methods. Consequently, it has only been possible up to now to produce plastic profiles which comprise sufficient wall thicknesses. 
       BRIEF SUMMARY OF THE INVENTION 
       [0007]    The object underlying the invention then is to create a method and a device for producing curved and straight thin-walled plastic profiles or hollow profiles. 
         [0008]    A method for achieving said object is a method for producing a thin-walled plastic profile where a continuous reinforcement produced from strands, woven fabric and/or the like is guided through a mold comprising at least one mold core and is embedded in the plastics material in the mold, characterized in that at least part of the mold is moved periodically relative to the stationary thin-walled plastic profile, and the thin-walled plastic profile is held by at least one holding means, which comprises a core and an outer holding part, whilst the mold is moved along. Accordingly, it is provided that at least part of a mold is moved periodically relative to the stationary thin-walled plastic profile and the thin-walled plastic profile is held by at least one holding means or gripper, which comprises a core and an outer holding part, whilst the mold is moved along the thin-walled plastic profile, which is stationary relative to the same. The plastic profile is preferably a hollow profile or a tubular profile produced from plastics material of arbitrary cross section. The holding means or the gripper is realized in such a manner that it completely surrounds the thin-walled plastic profile. The holding means preferably comprises at least two outer holding parts which surround the tubular profile in a complete, preferably partial, manner and are arranged about the tubular profile so as to be releasable. The joining together and moving apart of the outer holding parts is effected automatically or manually and is matched to the production process. The core, which is associated with the holding means, is situated in the interior of the plastic profile or of the tubular profile and corresponds in its form to the inside dimensions of the profile. The core of the holding means is fixed by a holding bar, in particular is coupled magnetically in a contactless manner with the holding parts. It is additionally provided according to the invention that the plastic profile hardens during the production process, in particular whilst it is in contact with at least part of the mold and/or is held by the holding means. As an alternative to this, however, it is also conceivable for the plastic profile not to harden, in particular only to harden in part, during the production process, in particular whilst it is in contact with at least part of the mold and/or is held by the holding means. The plastic profile is pulled out of the mold in a non-hardened or not completely hardened state and in a further step outside the mold and the holding means is moved into an end form in which it then hardens completely (pull-forming). In said case, the production is divided into two stages, namely into a pre-forming by the mold and an end forming by a further forming means. The further forming means can be, for example, a press. As a result of dividing the production process into two in this manner, more complex, individualized plastic profiles are able to be produced. 
         [0009]    It is provided in the case of a preferred development of the method that the holding means is arranged directly in front of or behind the mold along the thin-walled plastic profile or tubular profile when viewed in a pultrusion direction of the thin-walled plastic profile. The spacing between the holding means and the mold is modified by moving the mold and/or the holding means in an alternating, preferably periodic manner. As a result of said pilgering process, the mold and the holding means are moved alternately or together over the plastic profile, in a direction in opposition to the pultrusion direction, preferably in the pultrusion direction. When seen in the pultrusion direction, the mold and the holding means are arranged in front of a material store. The holding means is preferably positioned in front of the mold and in front of the material store and the mold is positioned behind the holding means. The plastic profile leaves the mold at an outlet area which is associated with a front end of the mold in the pultrusion direction. At an end of the mold located opposite the outlet area is situated an inlet area into which the material is pulled when the profile is being produced. The material gradually passes through the inlet area into the mold and the plastic profile gradually passes out of the outlet area of the mold again. The finished plastic profile is situated in front of the holding means when seen in the pultrusion direction. 
         [0010]    It is further provided that the at least one holding means is moved out of contact with the thin-walled plastic profile in phases in which at least part of the mold is stationary, preferably the outer holder of the holding part is moved out of contact with the thin-walled plastic profile, and is moved toward the mold in a direction opposite to a pultrusion direction relative to the stationary plastic profile. In this case, the core of the holding means is moved in the same manner as the outer holder. The relative positioning of the outer holder and of the core of the holding means does not change. The outer holder and the core of the holding means are moved to the same extent with reference to the thin-walled plastic profile. 
         [0011]    It is provided according to the invention that the at least one holding means is moved into contact with the thin-walled plastic profile in phases in which at least part of the mold is stationary relative to the thin-walled plastic profile. It is preferably provided that the outer holder of the holding means is moved into contact with the thin-walled plastic profile or the contact is eliminated again. Where they are in contact, a pressure is built up onto an outer wall of the profile. So that the profile does not kink or become damaged, a corresponding counter pressure, which compensates for the force of the holding parts onto the wall, is built up through the core of the holding means which is located in the interior of the profile. The force or the pressing pressure of the holding parts and the counter force of the core are so great that the profile is fixed in such a manner that it is not movable along the pultrusion direction. 
         [0012]    It is provided according to a further development of the method that to achieve a starting position of the pultrusion method at least part of the mold and the or each of the holding means, which comprise a core, are moved together with the plastic profile in the pultrusion direction. Said starting position is the start of a new pultrusion cycle. Where the mold, the holding means and the plastic profile are moved together, material for the next pultrusion step is removed from the material store. 
         [0013]    It is additionally provided in a preferred manner that that the at least one holding means, which comprises a core, is stationary and is moved out of contact with the thin-walled plastic profile and a front end of the mold is then moved together with the thin-walled plastic profile in the pultrusion direction into the vicinity of the holding means. The thin-walled plastic profile, in this case, is pushed over the core of the holding means. In the case of said alternative method step, the holding means is not moved. The holding parts and the core are still located at the same point and are not moved along the pultrusion direction. Rather, with the holding parts open, the plastic profile is pushed through by the holding means. The spacing between the mold or the outlet area of the mold and the holding means varies periodically between a maximum stroke position and a minimum stroke position. Said method is preferred for plastics materials where the material or the plastics material adheres and an ideal separating means is not present. 
         [0014]    In particular, the invention further provides that the core of the holding means is fed through at least part of the mold in the pultrusion direction, specifically to the region of the thin-walled plastic profile which is held by the outer holding part. It is additionally provided that, as an alternative to this, the core of the holding means is fed, in a direction in opposition to the pultrusion direction, to the region of the thin-walled plastic profile which is held by the outer holding part. When the core of the holding means is fed, in opposition to the pultrusion direction, to the outer holding part by the finished thin-wall plastic profile, this must be interrupted at regular portions. When the core of the holding means is fed to the region of the thin-walled plastic profile which is held by the outer holding part, by the mold in the pultrusion direction, the inner part of the mold or of the mold core must be provided in such a manner. 
         [0015]    It is provided according to a further development of the invention that a force, which opposes the force which acts onto the thin-walled plastic profile through the outer holding part, is generated by the core, in the interior of the thin-walled plastic profile. In particular, in the case of thin-walled profiles, it is important that the force, which is applied onto the thin-walled plastic profile by the outer holding part, is compensated for by a corresponding counter force. If the force of the outer holding part is not compensated for, this can result in destruction of the thin-walled plastic profile. Consequently, it is essential to the invention that the core of the holding part counters at least the force generated by the outer holding part in the interior of the hollow profile and that the core and the holding parts are always located at the same height with reference to the profile. 
         [0016]    It is preferably provided according to the invention that a force corresponding to the force generated by the outer holding part is generated by an expandable core of the holding means. As the core of the holding means is expandable in an arbitrary manner according to the invention, the counter force to the force generated by the outer holding part is variable. The force which counters the outer holding part is thus able to be adjusted in a flexible manner. 
         [0017]    It is further provided that the expandable core of the holding means is supplied by a holding bar, which is connected to the core, with a pressurized medium, corresponding to the force generated by the outer holding part. The pressurized medium can preferably be a gas, such as for example air, or a liquid. The pressure of the medium in the core can be varied in an arbitrary manner, in particular the medium can be pumped out of the core completely. The core, which preferably consists of a flexible plastics material, additionally comprises in its interior an expandable bellows in which the pressurized medium is situated. 
         [0018]    A further advantageous development of the present invention is that the plastic profile is held alternately by different holding means which are arranged one behind another on the thin-walled plastic profile, whilst the mold or the mold core is moved relative to the stationary thin-walled plastic profile. 
         [0019]    It is provided according to the invention that several, preferably two, holding means are arranged in front of the mold. The thin-walled plastic profile is radially profiled when held by at least one holding means. At least one of the holding means is profiled in such a manner that, when contacting the thin-walled plastic profile, it transfers said profiling or a negative of the profiling to the hollow profile. In this case it is provided that the profiling can have both a concave and a convex form. When the profiled holding part interacts with the expandable core, the thin-walled plastic profile can be acted upon individually with a profiling in a localized manner. The form of the expandable core is adapted such that the thin-walled plastic profile is fixed in a positive locking manner between the profiling of the holding means and the core. It is conceivable for a plurality of differently profiled holding parts to be arranged one behind another along the pultrusion direction and to imprint a complex profiling on the thin-walled plastic profile. 
         [0020]    A device for achieving the object named in the introduction is a device for producing a thin-walled plastic profile having a mold, which comprises at least one mold core, in which a continuous reinforcement of the plastic profile is embedded in liquid plastics material, characterized in that at least part of the mold is movable relative to the plastic profile along the same and, when viewed in a pultrusion direction, at least one holding means, which comprises a core and an outer holding part, for the plastic profile emerging from the mold is arranged in front of the mold. It is provided that at least part of the mold is movable relative to the plastic profile along the plastic profile and, when viewed in a pultrusion direction, at least one holding means, which comprises a core and an outer holding part, is arranged in front of the mold for holding the plastic profile which emerges out of the mold. 
         [0021]    It is further provided in a preferred manner that the respective holding means is realized for producing a releasable grip-type connection to the thin-walled plastic profile or hollow profile outside the mold, in particular in front of the mold when seen in the pultrusion direction, and preferably each holding means is movable relative to the thin-walled plastic profile. 
         [0022]    A further advantageous development of the present invention is that the core corresponds in its dimensioning to an inner cross section of the thin-walled plastic profile. It is additionally conceivable for a gap, preferably a narrow gap, to be arranged between the core and an inner wall of the thin-walled plastic profile. 
         [0023]    In addition, it is provided in particular that the core of the holding means comprises a holding bar which extends through at least part of the mold in the pultrusion direction, or extends through the thin-walled plastic profile in a direction in opposition to the pultrusion direction. 
         [0024]    The invention further provides that the core consists of a flexible material, preferably a plastics material which is variable in size as a result of a medium, preferably a gas or a liquid, via a feed line in the holding bar. The device has associated therewith a pump which pumps gas or a liquid into the core or out of the core depending on the production phase. A bellows, which is produced from a flexible material and is connected to the feed line, is situated in the interior of the core. The gas or the liquid flows or runs into said bellows. The expanding bellows presses against the flexible material of the core, as a result of which the counter pressure or the counter force to the force generated by the outer holding part is generated. 
         [0025]    It is further provided according to the invention that the flexible core of the holding means is adaptable to the form of the holding parts and is movable along the pultrusion direction through the holding bar in such a manner that different positions are actuatable in order to support the outer holding parts. In particular, where there are multiple holding means arranged one behind another it is essential that the core can be associated with the holding means holding the thin-walled plastic profile. 
         [0026]    It is provided according to the invention in particular that, when viewed in the pultrusion direction, two or more holding means are arranged in front of the mold, wherein at least one holding means comprises a profiled holding part and the holding means are operable independently of one another. It is provided in particular that the holding means are operable coupled together. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0027]    Preferred exemplary embodiments of the invention are explained in more detail below by way of the drawing, in which: 
           [0028]      FIG. 1  shows a schematic view of a first exemplary embodiment of a device according to the invention in a starting position, 
           [0029]      FIG. 2  shows a schematic view of a second exemplary embodiment of a device according to the invention in a starting position, 
           [0030]      FIG. 3  shows the device of  FIG. 1  after a first operating step which follows the starting position, 
           [0031]      FIG. 4  shows the device of  FIGS. 1 and 3  after a second operating step, 
           [0032]      FIG. 5  shows the device of  FIGS. 1, 3 and 4  after a third operating step, 
           [0033]      FIG. 6  shows the device of  FIGS. 1, 3 to 5  after a last operating step, 
           [0034]      FIG. 7  shows a second method example of a device according to the invention of  FIG. 1  in a starting position, 
           [0035]      FIG. 8  shows the device of  FIGS. 1 and 7  after a first operating step, 
           [0036]      FIG. 9  shows the device of  FIGS. 1, 7 and 8  after a second operating step, 
           [0037]      FIG. 10  shows the device of  FIGS. 1, 7 to 9  after a third operating step, 
           [0038]      FIG. 11  shows the device of  FIGS. 1, 7 to 10  after a fourth operating step, 
           [0039]      FIG. 12  shows  FIGS. 1, 7 to 11  after the last operating step, 
           [0040]      FIG. 13  shows a schematic view of a further exemplary embodiment of a device according to the invention, 
           [0041]      FIG. 14  shows the device of  FIG. 13  after a further operating step, 
           [0042]      FIG. 15  shows a schematic view of a further exemplary embodiment of a device according to the invention in a starting position, 
           [0043]      FIG. 16  shows the device of  FIG. 15  after a first operating step which follows the starting position, 
           [0044]      FIG. 17  shows the device of  FIGS. 15 and 16  after a second operating step, 
           [0045]      FIG. 18  shows the device of  FIGS. 15 to 17  after a third operating step, 
           [0046]      FIG. 19  shows the device of  FIGS. 15 to 18  after a fourth operating step and 
           [0047]      FIG. 20  shows the device of  FIGS. 15 to 19  in a last operating step. 
       
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0048]    The figures show schematic representations of the devices according to the invention which also serve for carrying out the method according to the invention. Said devices are pultrusion devices for producing plastic profiles  30 , in particular thin-walled plastic profiles, preferably tubular plastic profiles. The plastics material is preferably a thermosetting plastics material. 
         [0049]    Tubular plastic profiles  30  with arbitrary wall thicknesses are able to be produced using the schematically shown devices. The device shown in  FIG. 1  shows a mold  31  with a mold core  32  located therein which, as a result of their interaction, impart its tubular development to the plastic profile  30 . The invention is not limited to the plastic profile  30  only comprising one mold core  32 , rather it is also conceivable for the plastic profile  30  to comprise a more complex cross section which is produced with a plurality of mold cores  32 . The mold  31  and the mold core  32  can be moved parallel to a pultrusion direction  33  over or through the plastic profile  30  (indicated by arrows  34 ). 
         [0050]    When viewed in the pultrusion direction  33 , a holding means  35  ( FIG. 1 ) is situated in front of the mold  31  or in front of the mold core  32 . Said holding means  35  comprises an outer holding part  36  and a core  37 . The outer holding part  36  preferably consists of two parts and can be closed from the outside about the plastic profile  30  which emerges out of the mold  31 . By moving the outer holding parts  36  transversely with respect to the pultrusion direction  33  (indicated by arrows  38 ), the plastic profile  30  is able to be gripped, or released. With the outer holding parts  36  in the same position relative to the plastic profile  30 , the core  37  of the holding means  35  is situated in the interior of the plastic profile  30 . The diameter of the core  37  is dimensioned in such a manner that it corresponds precisely to the inside cross section of the plastic profile  30 . However, it is also conceivable for the outside diameter of the core  37  to be reduced slightly in relation to the cross section of the plastic profile  30 . The length of the core  37  corresponds to the length of the outer holding parts  36 . 
         [0051]    The core  37  is movable parallel to the pultrusion direction  33  by means of a holding bar  39  in the plastic profile  30 . In the case of the exemplary embodiment of the invention shown in  FIG. 1 , the holding bar  39  extends through the mold core  32 . This is possible if the mold core  32  has a corresponding development. 
         [0052]    A material store (not shown) for fibers, for example carbon fibers, woven fabric and/or knitted fabric or similar or for reinforcement is situated behind the mold  31  in a direction in opposition to the pultrusion direction  33 . Consequently, the fibers, woven fabric, the reinforcement, etc., are pulled into the mold  31  or the mold core  32  in a rear region  40  and leave said mold core again in a front region  41  where the molded plastic profile is gripped by the holding means  35 . This means the fibers etc., are pulled into the mold through the inlet area  50  of the mold  31  and leave the mold  31  again out of an outlet area  51 . The mold  31  can be heatable and/or coolable for more rapid hardening of the profile. 
         [0053]    If the nature of the mold core  32  does not allow the holding bar  39  to extend through the mold core  32  in the pultrusion direction  33 , the core  37  is held by the holding bar  39  from the front region  41  in a direction in opposition to the pultrusion direction  33  ( FIG. 2 ). Here, the holding bar  39  extends through the interior of the finished plastic profile  30 . 
         [0054]    The production of a thin-walled plastic profile  30  with the device according to  FIG. 1  is shown below by way of  FIGS. 3 to 6 . Said production of a thin-walled plastic profile  30 , which is described in  FIGS. 3 to 6 , can be transferred to the device according to  FIG. 2 . In the phase of the production of a thin-walled plastic profile  30  shown in  FIG. 3 , the outer holding parts  36  are moved in such a manner transversely with respect to the pultrusion direction  33  (indicated by the arrows  38 ) that they come into contact with the outer wall  42  of the plastic profile  30 . The plastic profile  30  is gripped in such a manner by the outer holding parts  36  that the plastic profile  30  is secured fixedly between the outer holding parts  36  and the core  37  of the holding means  35 . 
         [0055]    When the plastic profile  30  is secured between the outer holding part  36  and the core  37 , the mold  31  and the mold core  32  are moved along the plastic profile  30  in a direction in opposition to the pultrusion direction  33  and in this case pull fibers, woven fabric, reinforcement, knitted fabric etc. (not shown) into the inlet area  50  of the mold  31  ( 34 ) ( FIG. 4 ). The wall  42  of the tubular plastic profile  30  is formed at the same time. The most varied hollow-walled or tubular plastic profiles can be produced in this manner depending on the development of the mold  31  and of the mold core  32 . 
         [0056]    Once the mold  31  and the mold core  32  have covered a certain distance along the plastic profile  30 , the mold  31  or the mold core  32  stop ( FIG. 5 ). The holding means  35  then releases the plastic profile  30  by the outer holding parts  36  moving outward (indicated by the arrows  38 ) ( FIG. 5 ). 
         [0057]    In the last operating step, the plastic profile  30  is moved together with the mold  31  and the mold core  32  in the pultrusion direction  33  such that the mold  31  or the mold core  32  are once again in the vicinity of the holding means  35 . The plastic profile  30  together with the mold  31  and the mold core  32  are moved, in this case, parallel to the pultrusion direction  33  relative to the holding means  35  ( FIG. 6 ). The plastic profile  30 , the mold  31  and the mold core  32  are stationary relative to one another in the case of said operating step. When the plastic profile  30  is moved, further material is removed from the material store (not shown). The method described in  FIGS. 3 to 6  for producing a thin-walled profile is suitable in particular for adhesive profiles. 
         [0058]      FIGS. 7 to 12  show a further exemplary embodiment of the present invention. The method shown in  FIGS. 7 to 12  is described by way of the exemplary embodiment of the device according to  FIG. 1 . It can easily be transferred however, to the exemplary embodiment according to  FIG. 2 . The method described in  FIGS. 7 to 12  for the production of a thin-walled plastic profile is suitable in particular for ideal separating means, this means the fibers or the profile do not stick in the mold. 
         [0059]      FIG. 7  describes a starting position according to  FIG. 1 . The method shown in  FIGS. 7 to 9  is identical to the sequences in  FIGS. 3 to 5 . Consequently, reference is made to the above description. 
         [0060]    Once the mold  31  and the mold core  32  have formed the plastic profile  30  and the holding means  35  has opened ( FIG. 9 ), the outer holding part  36  and the core  37  move together in a direction in opposition to the pultrusion direction  33  toward the mold  31  or the mold core  32 . The distance which the mold  31  or the mold core  32  covers over the plastic profile  30  corresponds to the distance which has been covered by the mold  31  or the mold core  32  for the production of the plastic profile  30  ( FIG. 10 ). 
         [0061]    Once the holding means  35  has moved along the plastic profile  30  in a direction in opposition to the pultrusion direction  33 , the holding means  35  with its outer holding part  36  closes about the plastic profile  30  again ( FIG. 11 ). The plastic profile  30  is now fixedly gripped by the outer holding part  36  and the core  37 . 
         [0062]    In the next and last operating step, the holding part  35 , the mold  31 , the mold core  32  and the plastic profile  30  are moved together in the pultrusion direction  33 , by precisely one stroke  43  which the holding means  35 , the mold  31  and the mold core  32  have carried out beforehand in a direction in opposition to the pultrusion direction  33  ( FIG. 12 ); they are once again accordingly situated in their starting position shown in  FIG. 7 . The plastic profile  30  is pulled by the holding means  35  during said movement. In the case of the last operating step ( FIG. 12 ), the plastic profile  30 , the holding means  35 , the mold  31  and the mold core  32  are moved relative to the material store (not shown). 
         [0063]    A further exemplary embodiment of the invention is shown in  FIGS. 13 and 14 . In the case of said exemplary embodiment, the core  37  of the holding means  35  is realized in a flexible manner. The core  37  comprises a flexible outer covering  44 , the form of which can be changed in an arbitrary manner. A bellows  45  is situated in the interior of the outer covering  44 . Said bellows  45  is connected to a line  46 . Said line extends through the holding bar  39  and is connected to a pump which is not shown. A liquid or a gas is pumpable into the bellows  45  via said line  46 . When a gas or a liquid is pumped into the bellows  45 , the bellows  45  expands and transfers its outer form to the more solid outer covering  44  of the core  37 . Depending on the nature of the cross section of the plastic profile  30 , the form of the core  37  can thus be adapted as a result of expanding the bellows  45  or the outer covering  44 . In the phase of producing the thin-walled plastic profile  30 , in which the holding means  35  fixedly surrounds the plastic profile  30  ( FIG. 3 ,  FIG. 11 ), the outer holding part  36  consequently presses from the outside onto the wall  42  of the plastic profile and the expanded core  37  from the interior of the plastic profile  30  ( FIG. 14 ). The core  37  or the covering  44  or the bellows  45  can also be contracted again. It is advantageous particularly for the movement of the core  37  relative to the plastic profile  30  when the core  37  is contracted. The contraction of the core  37  can also be managed by means of the pump means (not shown). In this case, the gas or the liquid is pumped out of the bellows  45 . All further operating steps for producing the thin-walled plastic profile  30  run according to  FIG. 3 to 6 or 7 to 12 . 
         [0064]    A further embodiment of the present invention is shown in  FIGS. 15 to 20 . The device shown in  FIG. 15  for producing a thin-walled plastic profile  30 , along with the previously described holding means  35 , comprises a further second holding means  47 . A single common core  37  is associated with the holding means  35  and the second holding means  47 . The core which is common to the holding means  35  and  47  is realized according to the core described in  FIGS. 13 and 14 , as an expanding or contracting flexible core. It is provided according to the invention that at least one outer holding part  48  of the second holding means  47  comprises a concave or convex or arbitrary form on the side of the plastic profile. This means that the form of the outer holding part  48  of the second holding means  47  does not correspond to the form of the outer wall  42  of the plastic profile  30 . In the case of the exemplary embodiment shown in  FIG. 15 , the outer holding part  48  of the second holding means  47  comprises a convex profiling  49 . 
         [0065]    The method for producing a thin-walled plastic profile shown in  FIGS. 15 and 16  corresponds to the method in  FIGS. 3 to 6  with the exemplary embodiment of  FIGS. 13 and 14 . When the mold  31  and the mold core  32  and the plastic profile  30  are moved in the pultrusion direction  33  and when the holding means  35  is open, the core  37  is moved along the pultrusion direction  33  by the holding bar  39 . The core  37  is moved in a contracted state in such a manner along the pultrusion direction  33  that it corresponds in its position to the second holding means  47  ( FIG. 17 ). 
         [0066]    For the following pultrusion step, the second holding means  47  and the core  37  move into a starting position ( FIG. 18 ). In this connection, the plastic profile  30  is gripped by the second holding means  47 . The plastic profile  30  is deformed locally as a result of the profiling  49  of the outer holding part  48 . So that the plastic profile  30  is able to be held by the second holding means  47  even in the case of said local deformation, the flexible core  37  is inflated in such a manner that it corresponds to the profiling of the plastic profile  30  which was brought about by the second holding means  47 . In this way, the plastic profile  30  can be fixed by the second holding means  47  even with said local deformation and protected from an unwanted movement in a direction in opposition to the pultrusion direction  33  ( FIG. 19 ). 
         [0067]    Once the mold  31  or the mold core  32  has finished a new portion of the plastic profile  33 , the second holding means  47  is opened again and the contracted core  37  is fed to the holding means  35  in a direction in opposition to the pultrusion direction  33  ( FIG. 20 ). 
         [0068]    It is provided for all embodiments for the production of the plastic profile  30  that the profile  30  hardens in the mold  31  and/or in the holding means  35 . Hardening in the mold  31  is advantageous insofar as the plastic profile  30  cannot be deformed any more by the holding means  35 . However, it is also provided for all embodiments that the plastic profile  30  hardens outside the mold  31  or the holding means  35 . Consequently, no hardening or only partial hardening takes place in the mold  31 . As a result of the plastic profile  30  not yet being fully hardened, it can be moved into an end form (pull forming) as a result of a further forming means, such as a press (not shown). The plastic profile  30  then hardens completely in said end form state. 
         [0069]    The method for producing a thin-walled plastic profile is not fixed to the embodiment in  FIGS. 15 to 20 . Rather, it is provided according to the invention that a plurality of outer holding means is assigned to the plastic profile  30 , it being possible for each holding means to have an individual profiling. It is also possible to vary the sequence of the holding means to be used as a result of the arbitrarily expandable or contractible core. 
       LIST OF REFERENCES 
       [0000]    
       
           30  Plastic profile 
           31  Mold 
           32  Mold core 
           33  Pultrusion direction 
           34  Arrow 
           35  Holding means 
           36  Outer holding part 
           37  Core 
           38  Arrow 
           39  Holding bar 
           40  Rear region 
           41  Front region 
           42  Wall 
           43  Stroke 
           44  Covering 
           45  Bellows 
           46  Line 
           47  Second holding means 
           48  Outer holding part 
           49  Profiling 
           50  Inlet area 
           51  Outlet area