Entangled carbon-fiber nonwoven production method and assembly, three-dimensional-component nonwoven production method, and nonwoven fabric

Abstract

An entangled carbon-fiber non-woven production method for producing an entangled carbon-fiber non-woven fabric from carbon fibers up to a fiber length of 100 mm, with the following steps: supplying carbon fibers; loosening/combing apart and aerodynamically isolating the carbon fibers; aerodynamically calming the isolated carbon fibers; introducing the calmed and isolated carbon fibers into a vertically arranged air shaft ( 1 ), wherein the carbon fibers are introduced at the upper end ( 12 ) of the air shaft ( 1 ); mixing the carbon fibers within the air shaft ( 1 ) in a contactless manner by air whirling by means of a plurality of individual air flows; aerodynamically depositing the carbon fibers onto a moving mold or deposit surface ( 2 ) arranged below the air shaft ( 1 ), wherein the aerodynamic deposition is performed by means of suctioning below the mold or the deposit surface ( 2 ), wherein the air flows are varied and/or adjusted in the direction and/or intensity thereof and the air flows are produced and varied by means of one or more rotating and horizontally arranged air nozzles ( 14 ). The invention further relates to an entangled carbon-fiber non-woven production device, to a three-dimensional-component non-woven production method, and to a non-woven fabric

1 . A process for producing a carbon fiber non-woven fabric from carbon fibers up to a fiber length of 100 mm,
 comprising the steps of:   I. supplying carbon fibers;   II. loosening/combing and aerodynamic separating the carbon fibers;   III. aerodynamic calming the separated carbon fibers;   IV. introducing the calmed and isolated carbon fibers into a vertically arranged air shaft ( 1 ), wherein the introduction takes place at the upper end ( 12 ) of the air shaft ( 1 );   V. contactless mixing the carbon fibers within the air shaft ( 1 ) by means of a plurality of individual air swirling air streams;   VI. aerodynamic depositing the carbon fibers onto a moveable mold or a laying surface ( 2 ) arranged below the air shaft ( 1 ), wherein the aerodynamic depositing if facilitated by a suction below the mold or the laying surface ( 2 ),   wherein   the air flows are varied or adjusted in their direction and/or strength, and   the air currents are produced and varied by one or more rotating and horizontally arranged air nozzles ( 14 ).   
     
     
         2 . The process according to  claim 1 , wherein
 the suctioning (step VI.) is varied and/or adjusted in the suction power.   
     
     
         3 . The process according to  claim 1 , wherein
 the mold or the laying surface ( 2 ) is passed under the lower outlet ( 11 ) of the air shaft ( 1 ), wherein the passing is guided linear or spatially, and wherein the normal surface of the shape or laying surface ( 2 ) corresponds in sections to the perpendicular of the air shaft ( 1 ).   
     
     
         4 . The process according to  claim 1 , wherein
 the carbon fibers are cut during feeding by means of a cross-cutter.   
     
     
         5 . The process according to  claim 1 , wherein any one of the preceding claims,
 the carbon fibers are supplemented by thermal bonding fibers during feeding.   
     
     
         6 . The process according to  claim 5 , wherein
 after the application of the mixture consisting of carbon fibers and thermal bonding fibers to mold or laying surface ( 2 ), the thermal bonding fibers are partially melted by application of energy.   
     
     
         7 . A carbon fiber non-woven fabric production device for carbon fibers up to a fiber length of 100 mm, to carry out the carbon fiber non-woven fabric manufacturing processes according to  claim 1 ,
 comprising:
 a supply arrangement for carbon fibers and, optionally, a supply arrangement for thermal binding fibers; 
 a loosening/combing apart device or a fiber opener for combing, separating, loosening and/or releasing the carbon fibers; 
 an air shaft ( 1 ), wherein this is arranged vertically and wherein the carbon fibers are introduced at its upper end ( 12 ) and discharged at the lower end ( 11 ); 
 a transport and separation device for separating and transporting the separated carbon fibers from the loosening/combing apart device or the fiber opener to the air shaft ( 1 ), including: 
 including:
 a pipeline system ( 4 ); 
 an entry area of the pipeline system ( 4 ) to the loosening/combing apart device or a fiber opener; 
 a transport fan ( 41 ) inside the pipeline system for transport of the carbon fibers to the air shaft; 
 a calming section ( 42 ), arranged downstream of the transport fan ( 41 ), designed as a perforated tube, and 
 an introduction section ( 43 ) for the introduction of the carbon fibers into the air shaft ( 1 ); 
 
   a perforated deposit surface ( 2 ) arranged at the lower end ( 11 ) of the air shaft ( 1 ), in particular a conveyor belt, or a three dimensional shape for giving form to the carbon fibers to be deposited thereon;   a vacuum provided below the deposit shape or surface ( 2 ), and   an aerodynamic mixing system arranged in the air shaft ( 1 ) for mixing the carbon fibers wherein
 the aerodynamic system comprises a plurality of air nozzles ( 14 ) which generate a plurality of air streams, wherein the air streams are variable and/or adjustable in their direction and/or strength. 
   
     
     
         8 . The device according to  claim 7 , wherein
 the air nozzles ( 14 ) are rotated around one or more axes and/or swiveled and/or are designed differently in their nozzle outlet.   
     
     
         9 . The device according to  claim 7 ,
 air nozzles ( 14 ) are arranged on horizontally arranged and rotating rollers.   
     
     
         10 . The device according to  claim 7 , wherein
 the neck area and/or the pipe section has interior grooves and/or baffles which cause a circular movement of the carbon fibers.   
     
     
         11 . The device according to  claim 7 , wherein
 a robot arm device is provided below the air shaft ( 1 ) for the movement of the mold, wherein the robotic arm device allows three-dimensional movement of the mold below the air shaft ( 1 ).   
     
     
         12 . The device according to  claim 7 , wherein
 a heat source ( 15 ) is arranged at the lower end ( 11 ) of the air shaft ( 1 ) so that the thermal bonding fibers can be heated after application to the mold or the laying surface ( 2 ).   
     
     
         13 . A three-dimensional non-woven component manufacturing method for manufacturing a non-woven fabric for a three-dimensional part using a carbon fiber non-woven fabric production device according to  claim 7 , wherein
 a three-dimensional mold of the component to be produced is guided past a fiber output such that the fibers applied from the fiber output onto the site of deposit are applied in the orientation normal to the surface of the mold.   
     
     
         14 . The method according to  claim 13 , wherein
 the speed of movement of the mold and/or a suction of the device below the mold is varied.   
     
     
         15 . A non-woven fabric prepared by a carbon fiber non-woven fabric production process according to  claim 1 .