A thermoplastic composite structure is produced by extruding a bead of composite material to a desired cross sectional shape. An extruder extrudes the polymer bead containing reinforcing fibers, using a low compression first extruder stage where the polymer is mixed and de-gassed, and a high compression second stage where the polymer is consolidated and extruded. The cross sectional profile of the polymer bead may be altered using a variable extruder gate.

A thermoplastic composite structure is produced by extruding a bead of composite material to a desired cross sectional shape. An extruder extrudes the polymer bead containing reinforcing fibers, using a low compression first extruder stage where the polymer is mixed and de-gassed, and a high compression second stage where the polymer is consolidated and extruded. The cross sectional profile of the polymer bead may be altered using a variable extruder gate.

Various embodiments related to three dimensional printers, and reinforced filaments, and their methods of use are described. In one embodiment, a void free reinforced filament is fed into an extrusion nozzle. The reinforced filament includes a core, which may be continuous or semi-continuous, and a matrix material surrounding the core. The reinforced filament is heated to a temperature greater than a melting temperature of the matrix material and less than a melting temperature of the core prior to extruding the filament from the extrusion nozzle.

Pipe corrugators having opposed series of pushed mold blocks forming a moving mold tunnel are subject to significant thermal expansion and are designed with a thermal expansion gap. The present invention provides a method and apparatus for measuring changes in this expansion gap and preferably recognizing potential thermal issues before serious problems occur. A sensor is provided adjacent a mold block drive that preferably detects a time duration between sensing a trailing portion of a lead mold block and a leading edge of a following mold block separated from the lead mold block by the thermal expansion gap. This time duration in combination with a speed of the pushed mold blocks is used to calculate the size of the thermal expansion gap.

A film blowing machine for producing a film web from a recycled material having a.-an extruder for melting and homogenizing the recycled material into a melt, b. an annular die for extruding a film tube, c. a guide for a melt flow between the extruder and the annular die via an annular die melt pump, for conveying the melt to the annular die, d. a tube-forming zone for longitudinal and transverse drawing of the film tube, e. a cooling means for the film tube moving in the machine direction, f. a flattening unit on the other side of the tube-forming zone for flattening the film tube into a double layer film web, g. a pair of draw-off rollers on the other side of the cooling means for drawing off the film tube, and h. the extruder is designed as a twin-screw extruder.

A device may generate a multi-layer stack of sheets that may be adhered into a slab-shaped preform for thermal drawing. The sheets may include sublayers. Stacking the sub-layered sheets results in accumulation of layers in the final fabricated preform. The stacking process may use mechanical translation and conveyance to support placement of the sheets and fabrication of the stack.

A system for depositing a composite filler material into a channel of a composite structure includes an end-effector configured to extrude a bead of the filler material into the channel. The filler material can comprise a first group of relatively long fibers, a second group of relatively short fibers and a resin. A drive system is configured to move the end-effector relative to the channel, and a position sensor is configured to detect the position of the bead relative to the channel. A controller is configured to operate the drive system in response to the detected position and to operate the end-effector to heat and compress the filler material so as to orient the longer fibers in a substantially longitudinal direction relative to the channel and the shorter fibers in substantially random directions relative to the channel when the bead is extruded into the channel.

A three-dimensional printer uses its extruder and build platform to properly orient the build platform within a working volume. In a multi-point leveling operation, the extruder is moved to the z-axis origin at a number of x-y positions within the plane of the build platform, and the height of the build platform is adjusted to meet the extruder at the origin. If the build platform is a meltable material such as a plastic, then this leveling process must be performed while the extruder is cool. A homing operation may be performed periodically after leveling in order to realign the z-axis positions of the build platform and extruder. A non-meltable contact point may be usefully provided so that homing can be performed while the extruder is hot, such as immediately before a build or between a number of builds.

A resin film manufacturing apparatus according to an embodiment includes a film passing sensor for winding, provided on an inlet side of a winding machine and configured to detect passing of a conveyed resin film therethrough. When the manufacturing of the resin film is started, the driving of the winding machine is started after the film passing sensor for winding detects that the resin film has passed therethrough.

A device may generate a multi-layer stack of sheets that may be adhered into a slab-shaped preform for thermal drawing. The sheets may include sublayers. Stacking the sub-layered sheets results in accumulation of layers in the final fabricated preform. The stacking process may use mechanical translation and conveyance to support placement of the sheets and fabrication of the stack.