Method and device for the production of a plastic profile
View Patent ↗In the production of elongate plastic profiles ( 10 ), which usually takes place by the pultrusion process, the cured plastic profile ( 10 ) emerging from a die ( 14 ) is pulled through the stationary die ( 14 ) by a take-off device. This process only makes it possible to produce straight plastic profiles ( 10 ). The invention envisages producing curved plastic profiles ( 10 ) by using a die ( 14 ) corresponding to the curvature of the plastic profile ( 10 ). For moving the cured part of the plastic profile ( 10 ) out of the die ( 14 ), it is provided that the die ( 14 ) is moved back step by step in relation to the stationary plastic profile ( 10 ) counter to the direction of production ( 19 ). In order that the plastic profile ( 10 ) remains stationary in relation to the die ( 14 ) as this takes place, it is securely held outside the die ( 14 ) by a holding means ( 20 ) during the moving back of the die ( 14 ).
1. A process for producing a plastic profile ( 10 ) comprising a continuous reinforcement ( 11 ) comprising strands ( 13 ), comprising:
leading woven fabrics through a ring-shaped die ( 14 ; 21 ; 28 );
embedding the woven fabrics in a plastic ( 12 ) in the die ( 14 ; 21 ; 28 ) to form the plastic profile ( 10 );
holding the plastic profile ( 10 ) stationary relative to the die ( 14 ; 21 ; 28 ); and
periodically moving the die ( 14 ; 21 ; 28 ) in relation to the stationary plastic profile ( 10 ) by periodically moving the die ( 14 ; 21 ; 28 ) on and along the formed shape of the plastic profile,
wherein the periodic movement of the die ( 14 ; 21 ; 28 ) comprises a movement step in a direction of production ( 19 ) of the plastic profile ( 10 ) and a movement step counter to the direction of production ( 19 ) of the plastic profile ( 10 ).
2. The process as claimed in claim 1 , wherein the periodic movement of the die ( 14 ; 21 ; 28 ) further comprises moving the die ( 14 ; 21 ; 28 ) back and forth discontinuously or step by step, whereby a relative movement of the die ( 14 ; 21 ; 28 ) in relation to the plastic profile ( 10 ) takes place during a backward movement of the die ( 14 ; 21 ; 28 ) counter to the direction of production ( 19 ).
3. The process as claimed in claim 1 , further comprising:
moving the die ( 14 ; 21 ; 28 ) back on the plastic profile ( 10 ) a certain distance counter to the direction of production ( 19 ) during the movement of the die ( 14 ; 21 ; 28 ); and
keeping the plastic profile ( 10 ) stationary as the die is moved,
whereby, as a result of the die being moved, a piece of the plastic profile ( 10 ) emerges from the die ( 14 ; 21 ; 28 ) progressively with each working cycle.
4. The process as claimed in claim 2 , wherein, during the movement of the die ( 14 ; 21 ; 28 ) counter to the direction of production ( 19 ), a location ( 17 ) at which the plastic profile ( 10 ) has cured in the die ( 14 ; 21 ; 28 ) migrates between opposite end regions of the die ( 14 ; 21 ; 28 ), and the die ( 14 ; 21 ; 28 ) is moved in relation to the plastic profile ( 10 ) when the location ( 17 ) at which the plastic profile ( 10 ) has cured is located in the region of a rear end ( 15 ) of the die ( 14 ; 21 ; 28 ).
5. The process as claimed in claim 3 , wherein the die ( 14 ; 21 ; 28 ) is moved back in relation to the stationary plastic profile ( 10 ), along on the plastic profile ( 10 ), until the location ( 17 ) at which the plastic profile ( 10 ) has cured in the die ( 14 ; 21 ; 28 ) is located in the region of the front end ( 18 ) of the die ( 14 ; 21 ; 28 ), and flowable liquid plastic is fed to the die ( 14 ; 21 ; 28 ) at least during the moving back of the die ( 14 ; 21 ; 28 ) counter to the direction of production ( 19 ) of the plastic profile ( 10 ).
6. A process for producing a plastic profile ( 10 ) comprising a continuous reinforcement ( 11 ) comprising strands ( 13 ), in which woven fabrics are led through a die ( 14 ; 21 ; 28 ) and embedded in a plastic ( 12 ) in the die ( 14 ; 21 ; 28 ), wherein
the die ( 14 ; 21 ; 28 ) is periodically moved in relation to the stationary plastic profile ( 10 );
the die ( 14 ; 21 ; 28 ) is moved on and along the shape of the plastic profile ( 10 );
during the moving along of the die ( 14 ; 21 ; 28 ) on the plastic profile ( 10 ) that is stationary in relation to the same, the plastic profile ( 10 ) is securely held by at least one holding means ( 20 );
the plastic profile ( 10 ) is securely held during the movement of the die ( 14 ; 21 ; 28 ); and
in phases in which the die ( 14 ; 21 ; 28 ) is net stationary, at least one holding means ( 20 ; 22 , 23 ) is brought out of contact with the plastic profile ( 10 ) and moved in relation to the stationary plastic profile ( 10 ) in the direction of the likewise stationary die ( 14 ; 21 ; 28 ), is moved back counter to the direction of production ( 19 ), and, following the movement back of the die ( 14 ; 21 ; 28 ), the at least one holding means ( 20 ; 22 , 23 ) that is not in contact with the plastic profile ( 10 ) is moved into the vicinity of the front end ( 18 ) of the die ( 14 ; 21 ; 28 ), in relation to the plastic profile ( 10 ) that is stationary as it does so.
7. The process as claimed in claim 6 , wherein, to reach a starting position, the die ( 14 ; 21 ; 28 ), the or each holding means ( 20 ; 22 , 23 ) and the plastic profile ( 10 ) are moved in the direction of production ( 19 ).
8. The process as claimed in claim 1 , wherein the die ( 14 ; 21 ; 28 ) has a changeable curvature and the die ( 14 ; 21 ; 28 ) is formed into a desired curvature and, during the moving of the die ( 14 ; 21 ; 28 ), the reinforcement ( 11 ) is kept taut within the die ( 14 ; 21 ; 28 ).
9. A process for producing a plastic profile ( 10 ) comprising a continuous reinforcement ( 11 ) comprising strands ( 13 ), comprising: leading woven fabrics through a ring-shaped die ( 14 ; 21 ; 28 ); embedding the woven fabrics in a plastic ( 12 ) in the die ( 14 ; 21 ; 28 ) to form the plastic profile ( 10 ); periodically moving the die ( 14 ; 21 ; 28 ) on and along the formed shape of the plastic profile ( 10 ); securely holding the plastic profile ( 10 ) stationary relative to the die ( 14 ; 21 ; 28 ) during the movement of the die ( 14 ; 21 ; 28 ), whereby during the movement of the die ( 14 ; 21 ; 28 ), the die ( 14 ; 21 ; 28 ) is moved in relation to the stationary plastic profile ( 10 ); and moving the die ( 14 ; 21 ; 28 ) back and forth discontinuously or step by step during the periodic movement of the die ( 14 ; 21 ; 28 ), whereby a relative movement of the die ( 14 ; 21 ; 28 ) in relation to the plastic profile ( 10 ) takes place during a backward movement of the die ( 14 ; 21 ; 28 ) counter to the direction of production ( 19 ).
10. A process for producing a plastic profile ( 10 ) comprising a continuous reinforcement ( 11 ) comprising strands ( 13 ), comprising: leading woven fabrics through a ring-shaped die ( 14 ; 21 ; 28 ); embedding the woven fabrics in a plastic ( 12 ) in the die ( 14 ; 21 ; 28 ) to form the plastic profile ( 10 ); periodically moving the die ( 14 ; 21 ; 28 ) on and along the formed shape of the plastic profile ( 10 ); securely holding the plastic profile ( 10 ) stationary relative to the die ( 14 ; 21 ; 28 ) during the movement of the die ( 14 ; 21 ; 28 ), whereby during the movement of the die ( 14 ; 21 ; 28 ), the die ( 14 ; 21 ; 28 ) is moved in relation to the stationary plastic profile ( 10 ); and moving the die ( 14 ; 21 ; 28 ) back on the plastic profile ( 10 ) a certain distance counter to the direction of production ( 19 ) during the periodic movement of the die ( 14 ; 21 ; 28 ), whereby, as a result of the die being moved, a piece of the plastic profile ( 10 ) emerges from the die ( 14 ; 21 ; 28 ) progressively with each working cycle.
11. The process as claimed in claim 9 , wherein, during the movement of the die ( 14 ; 21 ; 28 ) counter to the direction of production ( 19 ), a location ( 17 ) at which the plastic profile ( 10 ) has cured in the die ( 14 ; 21 ; 28 ) migrates between opposite end regions of the die ( 14 ; 21 ; 28 ), and the die ( 14 ; 21 ; 28 ) is moved in relation to the plastic profile ( 10 ) when the location ( 17 ) at which the plastic profile ( 10 ) has cured is located in the region of a rear end ( 15 ) of the die ( 14 ; 21 ; 28 ).
12. The process as claimed in claim 10 , wherein the die ( 14 ; 21 ; 28 ) is moved back in relation to the stationary plastic profile ( 10 ), along on the plastic profile ( 10 ), until the location ( 17 ) at which the plastic profile ( 10 ) has cured in the die ( 14 ; 21 ; 28 ) is located in the region of the front end ( 18 ) of the die ( 14 ; 21 ; 28 ), and flowable liquid plastic is fed to the die ( 14 ; 21 ; 28 ) at least during the moving back of the die ( 14 ; 21 ; 28 ) counter to the direction of production ( 19 ) of the plastic profile ( 10 ).