CN117656456A

CN117656456A - Cutting device and 3D print head

Info

Publication number: CN117656456A
Application number: CN202211038499.6A
Authority: CN
Inventors: 季鹏凯
Original assignee: Yuanzhi Taicang 3d Technology Co ltd
Current assignee: Yuanzhi Taicang 3d Technology Co ltd
Priority date: 2022-08-29
Filing date: 2022-08-29
Publication date: 2024-03-08

Abstract

The invention discloses a cutting device and a 3D printing head, wherein the cutting device is used for cutting continuous silk materials, the continuous silk materials are configured to be conveyed along the axial direction of the cutting device, the cutting device comprises a cutting knife capable of rotating around a rotating axis, the position relationship between the rotating axis and the axis of the continuous silk materials is fixed, the cutting knife is provided with at least one cutting edge, and the position of the cutting edge is gradually changed relative to the rotating axis along the rotating direction of the cutting knife, so that the distance from the cutting edge rotating to the position corresponding to the axis of the continuous silk materials is gradually changed; the 3D printing head comprises a material pipe and a cutting device, wherein the material pipe is used for conveying a cut object, the material pipe is provided with a notch for exposing the cut object, the cutting edge rotates along with the cutting knife, and the cut object is cut at the notch. Compared with the prior art, the cutting device has the advantages of small cutting torque, simple structure, light weight, high reliability, good printing dynamic property or quality and the like.

Description

Cutting device and 3D print head

Technical Field

The invention belongs to the technical field of 3D printing, and particularly relates to a cutting device and a 3D printing head.

Background

3D printing is based on digital model files to build objects by layer-by-layer printing, where a melt extrusion process, FFF (Fused Filament Fabrication) or FDM, extrudes flowable print material through nozzles moving along a print path and stacks layers to form a three-dimensional model. According to the layer pattern information of the digital model file, the spray head and the platform relatively move in an XY plane, so that the spray head can reach any position in a certain area above the platform, the spray head extrudes printing materials at a proper speed until one layer of printing is finished while moving above the platform, the printing head and the printing platform are mutually far away from a certain distance, such as a layer thickness, after one layer of printing is finished, a new layer of printing is continuously printed, and the printing heads are stacked layer by layer until a three-dimensional entity is formed.

The printing material is typically a meltable thermoplastic material, construction slurry, food slurry or biological slurry, etc., and the construction slurry or biological medical slurry may not be heated. The printing can be performed by adopting continuous fiber materials, and a 3D printing model of the composite material can be realized. For continuous filament materials, such as continuous fiber materials, in the printing process, the continuous filament materials or fiber materials often need to be cut off when the areas where fibers are not required to be laid or layers or areas are replaced, a traditional mode adopts a mode of directly cutting by a cutting knife, a larger driving force is needed when the continuous filament materials or the fiber materials are cut, the power or the volume of a driving motor is increased, if the cutting knife is controlled to cut by a mode similar to scissors or a connecting rod, the structure, the volume and the weight of a cutting device are larger, the structure of a printing head is complex, the quality is large, and the reliability and the printing dynamic property or quality are influenced.

Disclosure of Invention

The invention aims to overcome the defects of a cutting device in the prior art that the cutting torque is large, the structure is complex, the quality is large, and the reliability and the printing dynamics or quality are influenced.

The invention solves the technical problems by the following technical scheme:

a first aspect of the present invention provides a cutting device for cutting a continuous filament configured to be conveyed in an axial direction thereof, characterized in that the cutting device comprises a cutting blade rotatable about a rotation axis, the rotation axis being fixed in positional relationship with the axis of the continuous filament, the cutting blade having at least one blade whose position is gradually changed with respect to the rotation axis in a rotation direction of the cutting blade so that a distance from the blade rotated to a position corresponding to the axis of the continuous filament is gradually changed.

In the technical scheme, the continuous filament is cut by adopting the mode of cutting knife rotation, and the cutting knife can be cut and reset by only controlling the rotation direction or rotation angle during working, so that the structure is simple and easy to control. The position of the cutting edge is gradually changed relative to the rotation axis, when the continuous silk material is cut, the cutting edge rotates along the extending direction of the cutting edge along with the cutting knife to scratch the continuous silk material, and meanwhile, the distance between the cutting edge and the axis of the continuous silk material is gradually changed, so that the cutting edge has a certain cutting stroke relative to the continuous silk material in the process, the cutting moment can be reduced, the reliability of cutting operation is improved, and the continuous silk material can be cut more efficiently; in addition, the cutting mode is not easy to cause deformation of the continuous silk material caused by overlarge stress in the cutting process, and is very beneficial to the shape maintenance of the continuous silk material, so that the cutting mode is also suitable for cutting materials with softer or very hard materials. Because the structure is succinct, can reduce the power, moment of torsion, volume or weight of the driver (such as motor or servo etc.) of drive cutting knife, this technical scheme is particularly suitable for the cutting of the continuous filament material of 3D printing based on the melt extrusion molding technology, can effectively reduce the volume and the weight of 3D print head, does benefit to the dynamic performance and the printing quality that promote 3D and print. Further, in this technical scheme, even the cutting edge produces certain opening after long-time use, not only can not produce adverse effect to its cutting efficiency, owing to the existence of opening moreover, when the cutting edge is drawn continuous silk material, can form the cutting effect of similar sawtooth to promote cutting efficiency.

In the present invention, the position or position corresponding to the continuous filament or the axis of the continuous filament refers to the point or area where the cutting edge of the cutting knife is nearest to the continuous filament; or a point or region where a plane passing through the axis of the continuous filament and generally coincident with the axis of rotation of the cutter intersects the edge of the cutter, or a normal or normal plane on the edge of the cutter at a position or location corresponding to the continuous filament or to the axis of the continuous filament intersects the axis of the continuous filament or continuous filament.

In the invention, the axis of the continuous filament refers to a line which is perpendicular to and intersected with the cross section in the slender continuous filament, and the optimal line is formed by the center point of the cross section of the continuous filament along the axial direction of the continuous filament; or the lines parallel to the length direction in the continuous filament material, or the lines where the silk threads of the fiber filaments in the continuous filament material are located, or the lines of the geometric shapes of the continuous filament material can be generated by moving along the cross section area of the continuous filament material.

Preferably, the blade is directed towards the axis of rotation, or the blade is directed away from the axis of rotation; the distance from the blade edge to the axis of rotation varies gradually in the direction of rotation of the cutter.

In this technical scheme, the cutting knife is blade form basically, and the cutting edge orientation is general along the blade plane direction of cutting knife, can effectively utilize cutting knife circumference length to guarantee cutting stroke, promotes the cutting effect. Moreover, in this technical scheme, the axis of rotation can guarantee very easily and the axial direction of continuous silk material transmission is roughly unanimous, arranges the cutting knife easily, and can save horizontal space. In addition, the cutting edge of the cutting knife is on the same plane, so that the cutting quality can be ensured.

Preferably, the distance from the position of the cutting edge corresponding to the axis of the continuous filament to the rotation axis is uniformly changed along with the rotation angle of the cutting knife; and/or the circumferential movement speed of the cutting knife at the position corresponding to the axis of the continuous filament is greater than the change speed of the distance from the rotation axis during the rotation of the cutting knife around the rotation axis.

In the technical scheme, the distance from the position of the cutting edge corresponding to the axis of the continuous filament to the rotation axis is uniformly changed along with the rotation angle of the cutting knife, so that the increase size of the radius of the cutting edge (namely the distance from the cutting edge to the rotation axis is changed) is the same every rotation unit angle of the cutting knife, and a more stable cutting process can be realized. The movement of the cutting edge at the position corresponding to the axis of the continuous filament has two components, one component is perpendicular to the radius direction or the circumferential direction around the rotation axis, and the other component is along the radius direction, and the movement speed of the cutting edge perpendicular to the radius direction is greater than the position change speed along the radius direction, which is equivalent to the amplification of the acting force through the force arm, so that the cutting acting force of the cutting knife on the continuous filament can be increased, and the cutting efficiency is improved. Or the feeding speed of cutting can be reduced, the stress of the continuous filament in the cutting process is smaller, and the continuous filament in the cutting process can be prevented from deforming.

Preferably, the shape of the blade is a section of a gradual curve;

further preferably:

the shape of the blade is a section of an involute, and preferably, the circle center of a base circle of the involute is positioned on the rotating axis;

or the blade is shaped as a segment of a planar spiral, preferably, the start point of the planar spiral is located on the rotation axis,

or the shape of the blade is a circle or an arc, and the center of the circle or the arc is positioned outside the rotation axis,

in the technical scheme, the cutting edge is gradually changed, so that the cutting stability can be ensured. The different shapes of the blade can meet different cutting requirements. When the cutting edge is round (eccentric circle relative to the rotation axis), the processing is more convenient, and the cost of the cutting knife is lower.

Preferably, said cutting tool has a blade for cutting one said continuous filament or simultaneous cutting of a plurality of said continuous filaments; preferably, a plurality of continuous filaments are sequentially arranged along the extending direction of the cutting edge, and the normal distances between the continuous filaments and the cutting edge are equal.

In the technical scheme, the cutting of a plurality of continuous filaments is realized through one cutting edge, so that the positions of the continuous filaments are different, but the continuous filaments can be cut off at the same time. Compact structure, reliable operation and high efficiency.

Preferably, said cutting tool has two said blades for cutting two different ones of said continuous filaments respectively:

when both the cutting edges face the rotation axis or both the cutting edges face a direction away from the rotation axis, the change trend of the distance between the two cutting edges and the rotation axis is opposite along the rotation direction of the cutting knife; preferably, the two cutting edges are linearly symmetrical with respect to a radial direction in which the cutter rotates; further preferably, two of the continuous filaments are respectively provided at positions corresponding to the cutting edges being closer to the rotation axis;

when the two cutting edges face to the direction of the rotating axis and the direction away from the rotating axis respectively, the change trend of the distance between the two cutting edges and the rotating axis is the same along the rotating direction of the cutting knife; preferably, the shapes of the two said blades are equidistant from each other; it is further preferred that the radiation passing through both of said continuous filaments passes through said axis of rotation and/or that both of said continuous filaments are arranged at the midpoint of the two said blades being equidistant from each other in their direction of extension or direction of rotation.

In the technical scheme, two cutting edges are skillfully arranged on one cutting knife, and the requirement of independent cutting of two cut parts at different positions can be met only by controlling the rotation of the cutting knife.

Preferably, the rotation axis is parallel to the axis of the continuous filament or is arranged at an angle within + -45 deg..

In this embodiment, the axis of rotation is preferably substantially parallel to the axis of the continuous strand. The cutting effect is best when the axis of rotation is parallel to the axis of the continuous filament. When the rotation axis and the axis of the continuous filament material have a certain included angle, for example, the rotation axis and the axis of the continuous filament material are arranged within a range of +/-45 degrees, the continuous filament material can be cut better.

Preferably, the blade faces in the axial direction of the rotation axis, the distance from the blade to the rotation axis is equal in the rotation direction of the cutter, and the position of the blade is gradually changed in the axial direction of the rotation axis.

In this technical scheme, the cutting knife is the ring type structure, and the annular cutting knife is equivalent to the formation of "curling" with blade type cutting knife, can reduce the volume of cutting knife greatly, and can let the axis of rotation of cutting knife and the axis of continuous silk material generally perpendicular or the angle setting, do benefit to the driver setting in the position of keeping away from continuous silk material (being away from the material pipe that is used for transmitting continuous silk material promptly), avoided the interference of driver and material pipe, also do benefit to and let the cutting knife be close to and cut in the clearance or the breach of deep into the material pipe, do benefit to the radius of rotation of reducing the cutting knife and then do benefit to the cutting torque that increases the cutting knife.

Preferably, the peripheral movement speed of the blade at a position corresponding to the axis of the continuous filament is greater than the change speed in the axial direction along the rotation axis during rotation of the cutter around the rotation axis.

In the technical scheme, the position corresponding to the continuous filament has two components in the movement of the blade, one component is in the axial direction along the rotation axis, and the other component is perpendicular to the rotation axis, and the direction is along the circumference around the rotation axis. The moving speed of the cutting edge perpendicular to the direction of the rotating axis is larger than the changing speed along the axial direction of the rotating axis, which is equivalent to amplifying the acting force through the force arm, so that the cutting acting force of the cutting knife on the continuous filament can be increased, and the cutting efficiency is improved. Or the feeding speed of cutting can be reduced, the stress of the continuous filament in the cutting process is smaller, and the deformation of the continuous filament in the cutting process can be prevented

Preferably, the blade is shaped as a section of a cylindrical helix or the blade is shaped as a section of the edge of a cylindrical chamfer.

In the technical scheme, the proper blade shape can be selected according to different cutting requirements. The processing of the blade shapes of the two structures is simpler.

Preferably, the blade is located on a side of the cutter blade that is closer to the axis of rotation, or the blade is located on a side of the cutter blade that is farther from the axis of rotation.

In this technical scheme, can be according to the relative position of cutting knife's cutting edge and cutting department, the shape of reasonable selection cutting edge to reach better cutting effect.

Preferably, the cutting tool has two said blades for cutting two said continuous filaments respectively:

when the two cutting edges face in the same direction of the rotation axis, the positions of the two cutting edges change in the rotation axis in opposite directions along the rotation direction of the cutter; preferably, both said blades are symmetrical with respect to a plane passing through said axis of rotation; further preferably, two of the continuous filaments are respectively provided at positions corresponding to the short protrusions of the blade toward the direction of the rotation axis;

when the two cutting edges face opposite directions of the rotation axis, the positions of the two cutting edges change in the rotation axis in the same direction along the rotation direction of the cutter; preferably, the shapes of the two blades are identical, and the distances between the two blades along the axial direction of the rotation axis are equal everywhere; further preferably, two of the continuous filaments are disposed in sequence along the axial direction of the rotational axis.

Preferably, the axis of rotation is perpendicular to the axis of the continuous filament or is disposed at an angle in the range of 45 ° -135 °.

In this technical scheme, when the cutting knife of ring type structure is adopted, the axis of rotation is best roughly perpendicular with the axis of continuous silk material. When the included angle between the rotation axis and the axis of the continuous filament is within the range of 45-135 degrees, the cutting effect is better. The cutting effect is best when the axis of rotation is perpendicular to the axis of the continuous filament.

Preferably, the blade is a smooth continuous blade or a serrated blade; preferably, the serrated height of the serrated edge is smaller than the diameter of the continuous filament material and/or the envelope formed at the top or tip of the serrations of the serrated edge is a segment of a gradual curve, preferably the gradual curve comprises an involute, a spiral or an eccentric circle.

In this technical solution, the blade may be a smooth continuous blade. The blade may have a structure with small serrations, i.e., a so-called serrated blade, which can achieve a cutting effect of faster, more regular cutting surface, or less cutting force.

Preferably, the cutting device further comprises a driver having a rotatable output shaft connected to the cutter to rotate the cutter; preferably, the drive comprises a servo, a stepper motor or a servo motor.

In this technical scheme, the servo or called steering engine is an output shaft rotation or limited angle swing actuator formed by combining a micro motor and a reduction gear system, and may further include a control board inside, which can generally precisely control the rotation angle, and may determine an actuator of a starting zero point, and generally control the rotation angle of the output shaft through a PWM (pulse width modulation) signal, for example, the control board integrated inside may be used to control the rotation angle of the output shaft, and may implement positive and negative angle swing or multi-turn rotation within a certain range, for example, when the output shaft returns to zero at a certain frequency or pulse width, the rotation of the output shaft is performed in one direction when the frequency or pulse width increases, and the rotation of the output shaft is performed in another direction when the frequency or pulse width decreases.

According to a second aspect of the invention, there is provided a 3D printhead comprising a tube for transporting said continuous filament, said tube being provided with a gap for exposing said continuous filament, and said blade rotating with said cutter and cutting said continuous filament at said gap.

Preferably:

the feeding pipes comprise a first feeding pipe and a second feeding pipe, the first feeding pipe and the second feeding pipe are coaxially arranged, a gap is arranged between the first feeding pipe and the second feeding pipe, the gap forms the gap, and continuous silk materials are conveyed from the first feeding pipe to the second feeding pipe;

or, a notch is formed in the side wall of the material pipe so that the continuous silk material is exposed at the notch, and the notch forms the notch;

or, a nozzle is arranged at one end of the material pipe, an extrusion opening of the nozzle is used for discharging the 3D printing head, and the extrusion opening forms the notch; preferably, the cutter is provided with a step structure between the blade and the position where the rotation axis passes through the cutter, so that the position where the rotation axis passes through the cutter is away from the extrusion port.

Preferably, when the blade is oriented toward the axis of rotation or the blade is oriented away from the axis of rotation; in the rotation direction of the cutter, when the distance from the cutting edge to the rotation axis is gradually changed:

the cutting knife is arranged on one side of the cutting knife, which faces the first material pipe, and the first material pipe end face is a plane; or the other end of the notch is provided with a second material pipe end face, the cutting edge is positioned at the edge of the cutting knife facing to one side of the second material pipe, and the second material pipe end face is in a plane.

Preferably, when the blade is directed in the axial direction of the rotation axis, the distance from the blade to the rotation axis is equal in the rotation direction of the cutter, and the position of the blade is gradually changed in the axial direction of the rotation axis:

the cutting knife is provided with a notch, a first feeding pipe is arranged at one end of the notch, the first feeding pipe is provided with a first feeding pipe end face which faces one side of the cutting knife along the rotating radial direction of the cutting knife, which is close to the rotating axis, and the first feeding pipe end face is a cylindrical surface or a spherical surface matched with the cutting knife;

or, the first material pipe end face is arranged at one end of the notch, faces to one side of the cutting knife, which is far away from the rotation axis, along the radial direction of the rotation of the cutting knife, and is a cylindrical surface or a spherical surface matched with the cutting knife;

or the other end of the notch is provided with a second material pipe end face, the second material pipe end face faces to one side of the cutting knife, which is far away from the rotation axis, along the radial direction of the rotation of the cutting knife, and the second material pipe end face is a cylindrical surface or a spherical surface matched with the cutting knife;

or the other end of the notch is provided with a second material pipe end face, the second material pipe end face faces to one side, close to the rotation axis, of the cutting knife along the rotating radial direction of the cutting knife, and the second material pipe end face is a cylindrical surface or a spherical surface matched with the cutting knife.

Preferably, the feeding pipe is provided with a cutting ring at the notch, the side wall of the cutting ring is provided with an inlet hole or an outlet hole corresponding to the feeding pipe, the cutting knife is arranged in the cutting ring and is in rotatable clearance fit with the cutting ring, the inner side surface of the cutting ring at the inlet hole or the outlet hole forms the first feeding pipe end surface, or the inner side surface of the cutting ring at the inlet hole or the outlet hole forms the second feeding pipe end surface.

In the technical scheme, the cutting machine can adapt to cutting of continuous silk material under different conditions, and has wide application range and flexible use. The end face of the material pipe is matched with the cutting knife, so that the cutting quality can be improved.

The invention has the positive progress effects that:

in the technical scheme, the continuous filament is cut by adopting the mode of cutting knife rotation, and the cutting knife can be cut and reset by only controlling the rotation direction or rotation angle during working, so that the structure is simple and easy to control. The position of the cutting edge is gradually changed relative to the rotation axis, when the continuous silk material is cut, the cutting edge rotates along the extending direction of the cutting edge along with the cutting knife to scratch the continuous silk material, and meanwhile, the distance between the cutting edge and the axis of the continuous silk material is gradually changed, so that the cutting edge has a certain cutting stroke relative to the continuous silk material in the process, the cutting moment can be reduced, the reliability of cutting operation is improved, and the continuous silk material can be cut more efficiently; in addition, the cutting mode is not easy to cause deformation of the continuous silk material caused by overlarge stress in the cutting process, and is very beneficial to the shape maintenance of the continuous silk material, so that the cutting mode is also suitable for cutting materials with softer or very hard materials. Because the structure is succinct, can reduce the power, moment of torsion, volume or weight of the driver (such as motor or servo etc.) of drive cutting knife, this technical scheme is particularly suitable for the continuous filament material that 3D based on melt extrusion molding technology printed like continuous fiber material's cutting, can effectively reduce the volume and the weight of 3D print head, does benefit to the dynamic performance and the printing quality that promote 3D and print. Further, in this technical scheme, even the cutting edge produces certain opening after long-time use, not only can not produce adverse effect to its cutting efficiency, owing to the existence of opening moreover, when the cutting edge is drawn continuous silk material, can form the cutting effect of similar sawtooth to promote cutting efficiency.

Drawings

FIG. 1a is a schematic front view of a cutting device of a blade cutter according to the present invention;

FIG. 1b is a schematic perspective view of the cutting apparatus of FIG. 1 a;

FIGS. 2a and 2b are bottom schematic views of the cutting device of FIG. 1a or 1b, wherein FIG. 2a is a state of feeding continuous filament material and FIG. 2b is a state of cutting the continuous filament material;

FIG. 3a is a schematic view showing a specific structure of a cutter according to the present invention;

FIG. 3b is a schematic view of a cutting edge curve of a cutting blade according to the present invention;

FIG. 4 is a schematic view of a dual inner and outer double edge cutter according to the present invention;

FIG. 5a is a schematic view of a symmetrical double-bladed cutting blade according to the present invention, with minimal edge radius at the point of symmetry;

FIG. 5b is a schematic view of another symmetrical double-bladed cutting blade of the present invention, with the largest radius of the blade at the point of symmetry;

FIG. 6a is a schematic view of a cutting blade with an eccentric circular blade according to the present invention;

FIG. 6b is a schematic view of a serrated edge cutter of the present invention;

FIG. 7a is a schematic cross-sectional view of a 3D printhead with a cutting device according to the present invention;

FIG. 7b is a schematic partial cross-sectional view of a cutting device area of the 3D printhead of FIG. 7 a;

FIG. 7c is an enlarged partial schematic view of a cutter region of the 3D printhead of FIG. 7 a;

FIG. 7D is a schematic partial cross-sectional view of the 3D printhead with the chip cutter of the present invention located at the extrusion orifice;

fig. 8a and 8b are bottom schematic views of fig. 7a or 7b, fig. 8a being a continuous filament conveying state, and fig. 8b being a cutting state;

fig. 9a and 9b are perspective views showing a cutting device of a circular (tubular) cutter according to the present invention, fig. 9c and 9d are side views showing the cutting device of the circular (tubular) cutter, fig. 9a and 9c are continuous filament feeding states, and fig. 9b and 9d are cutting states;

FIGS. 10a and 10b are schematic views of a bevel ring cutter according to the present invention, wherein FIG. 10a is a perspective view, and FIG. 10b is a side view;

FIGS. 11a and 11b are schematic views of a ring cutter with helical blades according to the present invention, wherein FIG. 11a is a schematic view of the inner side blade of the ring and FIG. 11b is a schematic view of the outer side blade of the ring;

FIGS. 12a and 12b are perspective views showing a cutting device for cutting the outside of an annular (tubular) cutter ring according to the present invention, FIGS. 12c and 12d are side views, FIGS. 12a and 12c are continuous filament feeding states, and FIGS. 12b and 12d are cutting states;

FIG. 12e is a schematic view of a cutting ring disposed outside of a cutting blade;

FIGS. 13a and 13b are schematic views of a cutting blade of the present invention having two cutting edges side by side along the direction of the axis of rotation of the cutting blade;

FIGS. 14a and 14b are schematic views showing a cutting apparatus employing the cutting blade of FIGS. 13a and 13b in accordance with the present invention;

FIG. 15a is a schematic view of a symmetrical double-bladed cutting device according to the present invention, with the blades extending the longest at the point of symmetry;

FIG. 15b is a schematic view of the symmetrical double-bladed cutting knife of FIG. 15a with the cutting edges extending the longest at the point of symmetry;

FIG. 16a is a schematic view of another dual-symmetrical dual-blade cutting device of the present invention, with the blade at the point of symmetry extending the shortest;

FIG. 16b is a schematic view of the symmetrical double-bladed cutting knife of FIG. 16a, with the blade extension at the point of symmetry being the shortest;

fig. 17 is a schematic partial cross-sectional view of an annular cutter of the present invention at the extrusion orifice of a 3D printhead.

Detailed Description

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following description will explain the specific embodiments of the present invention with reference to the accompanying drawings. It is evident that the drawings in the following description are only examples of the invention, from which other drawings and other embodiments can be obtained by a person skilled in the art without inventive effort.

A cutting device for cutting a continuous filament 20, the continuous filament 20 being configured to be conveyed in an axial direction thereof (the continuous filament 20 itself), the cutting device comprising a cutter 131 rotatable about a rotation axis 99, the rotation axis 99 being fixed in positional relationship with the axis of the continuous filament 20, the cutter 131 having at least one blade 1311, the position of the blade 1311 being gradually changed with respect to the rotation axis 99 in a rotation direction of the cutter 131 so that a distance from the blade 1311 rotated to a position corresponding to the axis of the continuous filament 20 is gradually changed. Preferably, the continuous filament comprises a continuous wire-like material or wire, such as a continuous fiber filament, a metal wire or an optical fiber, etc.

In the technical scheme, the continuous filament 20 is cut by adopting the mode of rotating the cutting knife 131, and the cutting and resetting of the cutting knife 131 can be realized only by controlling the rotating direction or the rotating angle during working, so that the structure is simple and the control is easy. The position of the blade 1311 gradually changes relative to the rotation axis, when the continuous filament 20 is cut, the blade 1311 slides across the continuous filament 20 along the extending direction of the blade 1311 along with the rotation of the cutting knife 131, and the distance between the blade 1311 and the axis of the continuous filament 20 also gradually changes, so that the continuous filament 20 is cut in, the blade 1311 has a certain cutting stroke relative to the continuous filament 20 in the process, the cutting moment can be reduced, the reliability of the cutting operation is improved, and the continuous filament 20 can be cut more efficiently; in addition, this cutting method also does not easily cause deformation of the continuous filament 20 due to excessive stress during cutting, and is very beneficial to maintaining the shape of the continuous filament 20, so that it is also suitable for cutting softer or very hard materials. Due to the simple structure, the power, torque, volume or weight of a driver (such as a motor or a server) for driving the cutter 131 can be reduced, and the technical scheme is particularly suitable for cutting continuous filament materials based on 3D printing of a melt extrusion molding process, can effectively reduce the volume and weight of a 3D printing head, and is beneficial to improving the dynamic performance and printing quality of 3D printing. Further, in the present technical solution, even if the blade 1311 generates a certain gap after long-time use, not only the cutting efficiency thereof will not be adversely affected, but also due to the existence of the gap, when the blade 1311 is scratched through the continuous filament 20, a cutting effect similar to saw teeth can be formed, thereby improving the cutting efficiency.

Cutting devices with cutting blades of blade-type construction are provided below by cutting device embodiments 1-5. Further, the cutting device has a blade 1311 facing the axis of rotation 99, or the blade 1311 faces away from the axis of rotation 99; the distance from the cutting edge 1311 to the rotation axis 99 varies gradually in the rotation direction of the cutter 131.

For the cutting blade 131 with the blade-type structure, the cutting blade 131 is basically in a blade shape, or the curve of the cutting edge 1311 of the cutting blade 131 is located on a plane, the cutting edge 1311 faces to the direction of the blade plane of the cutting blade 131, so that the circumferential length of the cutting blade 131 can be effectively utilized to ensure the cutting stroke, and the cutting effect is improved. Moreover, the rotation axis 99 can be easily ensured to be substantially coincident with the axial direction of the continuous filament 20 conveyance, the cutter 131 can be easily arranged, and the lateral space can be saved. In addition, the blade 1311 of the cutter 131 is on one plane, and the quality of cutting can be ensured.

Cutting device example 1:

fig. 1a to 3b illustrate a cutting device for cutting a continuous filament (the continuous filament 20 may be conveyed by a material pipe 50), a cutting blade 131 is disposed on an output shaft 89 of a driver 80, and the driver 80 may control the output shaft 89 to rotate along a rotation axis 99 thereof, such as the rotation shown by an arrow θ in fig. 1a, so as to drive the cutting blade 131 to rotate.

The cutter 131 has a blade structure having a blade 1311 at an edge, and a distance (i.e., a radius length) from the blade 1311 to the rotation axis 99 varies with a change in rotation angle, that is, gradually varies in a rotation direction of the cutter 131, for example, rotates clockwise with an arrow θ, and the radius of the blade 1311 increases. The cutting edge 1311 of the cutting blade 131 faces the rotational axis 99 of the cutting blade 131 or the cutting edge 1311 faces away from the rotational axis 99 of the cutting blade 131; as the cutter 131 rotates about the rotation axis 99, the distance from the position of the cutting edge 1311 corresponding to the axis of the continuous wire 20 to the rotation axis 99 of the cutter 131 gradually changes. In fig. 1a, 1b and 2a, the cutting blade 131 is in a state in which the cutting edge 1311 has not hit the continuous filament 20 yet, and the continuous filament 20 can be continuously conveyed downward without being affected by the cutting blade. When the cutter rotates clockwise along arrow θ, the cutter rotates to the state shown in fig. 2b, a part of the large-radius blade 1311 is transferred to the position of the continuous filament 20 along with the rotation, when the cutter rotates to a certain angle, the large-radius blade 1311 contacts the continuous filament 20, and the cutter continues to rotate, the larger-radius blade 1311 cuts into the continuous filament, and then the continuous filament 20 can be completely cut off along with the continuous rotation of the cutter and the cutting of the larger-radius blade. The cutter 131 can then be rotated back in the opposite direction (e.g., counter-clockwise) to the condition shown in fig. 2a, the cutter avoiding the continuous filament 20, and the continuous filament 20 can again be conveyed along the tube 50. Of course, it is also possible to continue the rotation of the cutter, such as clockwise, until the rotation is restored to the condition shown in fig. 2a, i.e. the continuous filament is avoided, the blade 1311 is again brought closer to the continuous filament, and the continuous filament 20 is conveyed downward again and ready for the next rapid cutting.

In this embodiment, as shown in fig. 3b, the shape of the cutting edge 1311 of the cutting blade 131 is a section of a planar progressive curve 901, which may be a planar spiral, an involute, or a circular arc, etc., and it is further preferable that if the progressive curve adopts a planar spiral or an involute, the starting point (center point) may be located on the rotation axis 99. Of course, the cutting edge 1311 of the cutting blade 131 may be other forms, for example, in other embodiments, the shape of the cutting edge 1311 of the cutting blade 131 may be a segment of an involute, and it may be preferable that the center of the base circle of the involute is located on the rotation axis 99. Alternatively, the shape of the edge 1311 of the cutting blade 131 may also be an eccentric circular configuration (i.e. the centre of the circle is offset from the axis of rotation 99) as in fig. 6a, the axis of rotation 99 being at a position eccentric to the circular edge 1311. In practical application, the proper blade shape can be selected according to different cutting requirements.

The blade in the embodiments of the present invention may be either a smooth continuous blade structure or a structure with tiny serrations, so-called serrated blades, as shown in fig. 6b, which can achieve a faster, more clean cut surface or less cutting force cutting effect, and optimally, the height h of the serrations as shown in fig. 6b may be smaller than the diameter or radius of the continuous filament 20, and the envelope formed at the tip or tip of the serrations may be part of an involute, spiral or eccentric circle as a gradual curve.

As shown in fig. 3b, further, the distance from the cutting edge 1311 to the rotation axis 99 is uniformly changed with the rotation angle of the cutting blade 131 (the distance from the position of the cutting edge 1311 corresponding to the axis of the continuous filament 20 to the rotation axis 99 is uniformly changed with the rotation angle of the cutting blade 131), and the increase size of the radius of the cutting edge 1311 is the same every unit angle of rotation of the cutting blade 131, so that a smoother cutting process can be realized. Further, during rotation of the cutter 131, the circumferential movement speed of the blade 1311 is greater than the change speed of the distance of the blade 1311 from the rotation axis 99 at a position corresponding to the continuous filament 20. At a position corresponding to the axis of the continuous filament 20, the movement of the blade 1311 has two components, one component is a direction perpendicular to the radius or a circumferential direction around the rotation axis 99, and the other component is along the radius direction, and by making the movement speed of the blade 1311 perpendicular to the radius direction greater than the change speed along the radius direction, which is equivalent to amplifying the acting force by the arm of force, the cutting acting force of the cutter 131 on the continuous filament 20 can be increased, the cutting efficiency can be improved, or the feeding speed of cutting can be reduced, the continuous filament stress in the cutting process is smaller, and the continuous filament deformation in the cutting process can be prevented.

In fig. 3b and 3a, it is also possible to provide a shaft hole 1312 in the cutter 131 so that it can be fitted over the output shaft of the driver 80, as in fig. 1b to 2b the cutter 131 can be fixed to the output shaft 89 by means of a screw 68. Splines 1313 may also be provided in the shaft bore 1312 to mate with external splines on the output shaft 89 of the server shown in FIG. 1 b. It is understood that the connection between the cutter 131 and the output shaft 89 is not limited to the connection in this embodiment, and other connection methods such as key connection and the like or other connection methods may be adopted.

The actuator 80 shown in fig. 1b may be a servo (servo), which is an actuator that uses a combination of a micro motor and a reduction gear system to form an output shaft rotating or swinging at a limited angle, and is generally capable of precisely controlling the rotating angle, and determining the starting zero point, and is generally controlled by PWM signals, and is generally used for rudder driving in unmanned aerial vehicles or steering driving in remote control automobiles, and has light weight, small volume and large torque. Of course, it is understood that in other embodiments, the driver 80 may employ a stepper motor, a servo motor, or the like.

In this embodiment, further, the continuous filament 20 is conveyed by the pipe 50 in a straight line, and the axis of the continuous filament 20 or the pipe 50 is substantially parallel to the rotation axis of the cutter.

Cutting device example 2:

the cutting device of this embodiment is substantially the same as the cutting device of embodiment 1, except that the cutting device of this embodiment is used for cutting two continuous filaments 20, as shown in fig. 3b, the two continuous filaments 20 are sequentially arranged along the extending direction of the cutting edge 1311, and the normal distances between the two continuous filaments 20 and the cutting edge 1311 are equal.

Thus, when the cutter 131 rotates clockwise (or in a direction of increasing radius) as in fig. 3b, the positions of the two continuous filaments 20 are simultaneously cut although they are different, so that the cutting of the two continuous filaments is simultaneously achieved by one blade 1311, so that the positions of the two continuous filaments are simultaneously cut although they are different. Compact structure, reliable operation and high efficiency. Generally, the continuous filament is fed within the tube, the cutter 131 is rotatable about an axis of rotation 99 generally perpendicular to the blades, and the distance (radius) of the blade edge 1311 from the axis of rotation 99 increases or decreases with increasing rotation angle, with the axis of the continuous filament 20 (i.e., the axis of the tube 50) being generally parallel to the cutter axis of rotation 99. When the cutting knife 131 is rotated, the radius of the cutting edge 1311 is increased until the part with the radius larger than the distance from the continuous filament 20 to the rotation axis 99 corresponds to the continuous filament 20, so that the cutting is realized; alternatively, when the cutting edge 1311 of the cutter 131 is oriented in the direction of the rotation axis of the cutter, the portion having a radius larger than the distance from the continuous filament 20 to the rotation axis 99 of the cutter 131 corresponds to the continuous filament 20 when not cutting, and when cutting, the cutter 131 is rotated so that the radius of the cutting edge 1311 is reduced until the portion having a radius smaller than the distance from the continuous filament 20 to the rotation axis 99 corresponds to the continuous filament 20, effecting cutting.

In other embodiments, more continuous filaments 20 may be provided, and the continuous filaments 20 need to be equidistant from the normal distance of the blade 1311. Of course, the normal distance from the two continuous filaments to the cutting edge can be different, so that the cutting sequence of the two continuous filaments can be correspondingly realized.

Cutting device example 3:

the cutting device of this embodiment is substantially the same as the cutting device of embodiment 1, except that in this embodiment, the cutter blade 131 has two blades 1311a and 1311b, and the two blades 1311a and 1311b are respectively used for cutting two different continuous filaments (the first continuous filament 201 and the second continuous filament 202), and further, in this embodiment, the two blades 1311a and 1311b are respectively oriented in a direction away from the rotation axis 99 and in a direction toward the rotation axis 99, and the trend of the distance of the two blades 1311 to the rotation axis 99 is the same along the rotation direction of the cutter blade 131.

As shown in fig. 4, for example, the cutting edges 1311a and 1311b may be part of the involute or spiral lines 901a and 901b, respectively, and the lines 901a and 901b may be equidistant curves (offsets) from each other. The blade 1311a is disposed opposite the blade 1311b, with the blade 1311a facing away from the shaft bore 1312 (or the axis of rotation 99) and the blade 1311b facing toward the shaft bore 1312 (i.e., the axis of rotation 99). Further, the wire rays of the first continuous filament 201 and the second continuous filament 202 arranged pass through the shaft hole 1312 (or the rotation axis 99), and further, the first continuous filament 201 and the second continuous filament 202 are disposed at the midpoint of the blade 1311a or 1311b in the extending direction (or the rotation direction) of the blade. Thus, when the cutter 131 rotates clockwise, the radii of the blades 1311a and 1311b are increased, the inner blade 1311a cuts the first continuous wire 201, and the outer blade 1311a moves away from the second continuous wire 202, so that the second continuous wire 202 may not be cut. When the cutter 131 rotates counterclockwise, the radii of both edges 1311a and 1311b decrease, the inner edge 1311a will move away from the first continuous wire 201, the first continuous wire 201 may not be cut, and the outer edge 1311a will cut the second continuous wire 202. Thus, by means of one cutting knife, independent cutting control of the two continuous filaments (the first continuous filament 201 and the second continuous filament 202) can be achieved.

In this embodiment, two pipelines may be disposed in the material pipes 50 for conveying the filaments 201 and 202, or two material pipes 50 may be disposed in each material pipe 50, and each material pipe 50 is provided with a feeding pipeline, and the two pipelines respectively convey the continuous filaments 201 and 202.

Cutting device example 4:

the present embodiment is substantially the same as the cutting device embodiment 1, except that in the present embodiment, the cutter 131 has two blades 1311a and 1311b, the two blades 1311a and 1311b are respectively used for cutting two different continuous filaments (the first continuous filament 201 and the second continuous filament 202), further, in the present embodiment, both blades face away from the rotation axis 99, and the change trend of the distance of the two blades 1311a and 1311b to the rotation axis 99 is opposite in the rotation direction of the cutter 131.

In this embodiment, fig. 5a illustrates that two blades 1311a and 1311b of the two segments facing outward (toward away from the axis of rotation 99) may be positioned symmetrically up and down with respect to the figure. The cutting edge at the symmetry point in fig. 5a is closest to the shaft hole 1312, so that the first continuous filament 201 and the second continuous filament 202 are also disposed relatively close to the symmetry point with respect to the up-down symmetry, and at this time, the first continuous filament 201 and the second continuous filament 202 are disposed at positions corresponding to the positions of the two cutting edges 1311a and 1311b closest to the rotation axis 99, respectively, such that when the cutting blade rotates clockwise, the radius of the cutting edge 1311b at the position corresponding to the second continuous filament 202 increases to cut the second continuous filament 202, and the radius of the cutting edge 1311a at the position corresponding to the first continuous filament 201 decreases to cut the first continuous filament 201. If the cutter continues to rotate clockwise, the blade edge 1311b may further also cut the first continuous filament 201. When the cutter rotates counterclockwise, an increase in the radius of the blade 1311a at a position corresponding to the first continuous wire 201 cuts the first continuous wire 201, and a decrease in the radius of the blade 1311b at a position corresponding to the second continuous wire 202 does not cut the second continuous wire 202. If the cutter continues to rotate counter-clockwise, the blade 1311b may further also cut the first continuous filament 201.

Cutting device example 5:

the cutting device in this embodiment is substantially the same as embodiment 4 of the cutting device, except that in this embodiment, as shown in fig. 5b, two outwardly facing blades 1311a and 1311b may be disposed symmetrically up and down with respect to the drawing, and the blade at the point of symmetry is farthest from the shaft hole 1312, so that the first continuous filament 201 and the second continuous filament 202 are disposed at positions separated by the point of symmetry with respect to the symmetry, and at this time, the first continuous filament 201 and the second continuous filament 202 are disposed at positions corresponding to the positions of the two blades 1311a and 1311b closer to the rotation axis 99, respectively, such that when the cutter rotates clockwise, the radius of the blade 1311a increases at the position corresponding to the first continuous filament 201 and the second continuous filament 202 is cut, and the radius of the blade 1311b decreases at the position corresponding to the second continuous filament 202. When the cutter rotates counterclockwise, an increase in the radius of the blade 1311b at a position corresponding to the second continuous wire 202 cuts the second continuous wire 202, and a decrease in the radius of the blade 1311a at a position corresponding to the first continuous wire 201 does not cut the first continuous wire 201.

Cutting device embodiments 6 to 9 provide a cutting device in which the cutter 131 is of a ring type structure. Further, the distance from the blade 1311 to the rotation axis is equal in the axial direction of the rotation axis 99 along the rotation direction of the cutter 131, and the position of the blade 1311 gradually changes in the axial direction of the rotation axis. The cutting blade 131, which may be of a ring or tubular configuration, may be part of a ring or tube, with the cutting edge being located on the annulus of the ring or tube, or with the curve of the cutting edge of the cutting blade being located on the annulus.

The annular cutter is equivalent to the "curling" of the blade cutter, which can greatly reduce the volume of the cutter 131, and can make the rotation axis 99 of the cutter 131 substantially perpendicular to or at an angle to the axis of the continuous filament 20, so that the driver 80 is advantageously arranged at a position far away from the continuous filament 20 (i.e. far away from the material pipe 50 for conveying the continuous filament 20), interference between the driver 80 and the material pipe 50 is avoided, and the cutter 131 is also advantageously made to approach and penetrate into a gap or a notch of the material pipe 50 for cutting, which is advantageous for reducing the rotation radius of the cutter 131 and further increasing the cutting torque of the cutter 131.

Cutting device example 6:

the same parts of the cutting device in this embodiment as those of the cutting device in embodiment 1 will not be described again. The difference is that the cutter blade is a ring type structure as shown in fig. 9a to 10b, the cutter blade 131 is a ring blade type structure as shown in fig. 10a, the blade 1311 is at the top end of the ring blade, and the shaft hole 1312 may be provided at the root. The distance of the edge 1311 from the blade root in the axial direction of this annular blade varies with the angle of rotation (i.e. the position of the edge 1311 varies gradually in the axial direction of the axis of rotation 99 towards one end), for example optimally increasing, or the edge 1311 of the cutting blade 131 is oriented in the axial direction of the axis of rotation 99 of the cutting blade 131, the distance of the edge 1311 from the axis of rotation 99 being equal in the direction of rotation of the cutting blade 131, the position of the edge 1311 corresponding to the axis of the continuous filament 20 varying gradually in the axial direction of the axis of rotation 99, in which embodiment the projection of the edge 1311 in the lateral direction may be a diagonal line (i.e. the shape of the edge 1311 is a segment of the edge of a cylindrical chamfer) as shown in fig. 10 b. Of course, the blade 1311 of the cutting blade 131 may also be of other forms, for example in other embodiments, as shown in fig. 11a and 11b, the blade shape may be a section (part) of a cylindrical helix 902.

In this embodiment, the cutting edge 1311 may be on the inside of the ring bending blade (as shown in fig. 10a and 11 a), i.e., the cutting edge 1311 is located on the side of the cutting blade 131 near the axis of rotation 99, and the embodiment of fig. 9a to 9d in this example may employ a cutting blade configuration of the inside cutting edge, as shown in the embodiments of fig. 10a and 11 a.

Further, during rotation of the cutter 131, the circumferential movement speed of the blade 1311 of the cutter 131 at a position corresponding to the axis of the continuous filament 20 is greater than the change speed in the axial direction along the rotation axis 99. I.e., at a position corresponding to the continuous filament 20, the movement of the blade 1311 has two components, one component being in the axial direction along the rotational axis 99 and the other component being in a direction perpendicular to the rotational axis 99 and also generally perpendicular to the axis of the continuous filament 20, which is in the circumferential direction about the rotational axis 99. By making the moving speed of the blade 1311 perpendicular to the direction of the rotation axis 99 greater than the changing speed along the axial direction of the rotation axis 99, which is equivalent to amplifying the acting force through the arm of force, the cutting acting force of the cutting knife 131 on the continuous filament can be increased, and the cutting efficiency can be improved. Further, the axis of the continuous filament 20 is substantially perpendicular to the rotational axis 99 of the output shaft 89 (or the axis of the shaft hole 1312 of the cutter 131).

In fig. 9a, the cutter 131 is shown sleeved and fixed on the output shaft 89 of the driver 80, for example, the driver 80 may be a servo (servo) or a stepper motor or a servo motor. The driver 80 drives the cutter 131 to rotate clockwise along the arrow in fig. 9b or 9d so that the length of the extension of the blade of the cutter corresponding to the corresponding position of the continuous filament 20 in the direction of the continuous filament increases, and the continuous filament is cut. The continuous filament 20 is cut off as in fig. 9b or 9d, and then the cutter may be rotated counterclockwise or rotated further clockwise back to the original state avoiding the continuous filament 20, as shown in fig. 9a and 9c, and the continuous filament may be conveyed downward again.

Of course, it is understood that in other embodiments, as shown in fig. 11, the blade 1311 may also be outboard of the ring bending blade, as shown in fig. 11b, with the blade 1311 being located on the side of the cutting burr 131 remote from the axis of rotation 99. Fig. 12a illustrates a cutter structure using an outer blade, as in the cutter shown in fig. 11b, in fig. 12a and 12c, the cutter is in a state of avoiding the continuous filament 20, and the continuous filament can be continuously conveyed, and when cutting is required, the cutter 131 is rotated clockwise as in fig. 12b or 12d, so that the length of the blade extending axially toward the continuous filament along the cutter rotation axis at the position corresponding to the continuous filament increases, cutting the continuous filament 20. After cutting is completed, the cutter may continue to rotate clockwise or counter-clockwise until the cutter is in a state of avoiding continuous filament as shown in fig. 12a or 12c, and continuous filament transfer is performed.

The blade in this embodiment may have a smooth continuous blade structure or may have a structure with fine serrations, so-called serrated blade.

Cutting device example 7:

the cutting device in this embodiment is substantially the same as the cutting device embodiment 6 except that the cutter 131 in this embodiment has two blades 1311a and 1311b, and the two blades 1311a and 1311b are used for cutting two different continuous filaments (the first continuous filament 201 and the second continuous filament 202), respectively. Further, the two blades 1311a and 1311b are oriented in different directions of the rotation axis 99, and the positions of the two blades 1311a and 1311b in the rotation direction of the cutter 131 have the same tendency to change on the rotation axis 99.

In this embodiment, the cutter 131 adopts a double-blade structure as shown in fig. 13a and 13b, the blade 1311a faces away from the shaft hole 1312, the blade 1311b faces toward the shaft hole 1312, and the two blades may be curves translating with each other. Further, fig. 14a and 14b illustrate that the planes defined by the axes of the first continuous filament 201 and the second continuous filament 202 are optimally coincident with or parallel to the rotational axis 99 of the cutting blade. Thus, when the cutter 131 rotates clockwise, the extended length of the cutting blade 1311a and the cutting blade 1311b along the cutter rotational axis 99 is reduced at the position corresponding to the position of the material pipe 50 (or the position of the continuous filament), and the cutting blade with the reduced extended length along the rotational axis 99 of the cutter 131 cuts the second continuous filament 202 because the cutting blade 1311a is positioned on the side of the first continuous filament 201 closer to the shaft hole 1312 and the cutting blade 1311b is positioned on the side away from the shaft hole 1312 relative to the second continuous filament 202. When the cutter 131 rotates counterclockwise, the extended length of the blade 1311a and the blade 1311b along the cutter rotation axis 99 increases corresponding to the position of the material pipe (or the position of the continuous filament), and since the blade 1311a is on the side of the first continuous filament 201 near the shaft hole 1312, the blade with the increased extended length along the axial direction of the rotation axis 99 of the cutter 131 cuts the first continuous filament 201, whereas the blade 1311b is on the side away from the shaft hole 1312 with respect to the second continuous filament 202, and does not cut the second continuous filament 202. The cutting knife can realize independent cutting control of two continuous silk materials respectively in a positive and negative rotation mode. Compact structure, reliable operation, quick response and convenient arrangement.

Cutting device example 8:

this embodiment is substantially the same as embodiment 7 of the cutting device, except that in this embodiment, the two blades 1311a and 1311b face the same direction of the rotation axis 99, and the positions of the two blades 1311a and 1311b in the rotation direction of the cutter 131 have opposite tendencies to change on the rotation axis 99.

In this embodiment, fig. 15a and 15b show that the cutting blade may be symmetrically arranged with two blades, for example, further, the blades 1311a and 1311b are symmetrically arranged with respect to a plane passing through the rotation axis 99 of the cutting blade 131 (i.e. symmetry plane), the two continuous filaments (first continuous filament 201 and second continuous filament 202) are respectively arranged at both sides of the symmetry plane, and optimally are downwardly conveyed in a direction parallel to the symmetry plane, and the intersection of the two blades 1311a and 1311b in fig. 15a and 15b has a maximum blade extension length, and in fig. 15a, the two pipes 50 each have a pipe for conveying the continuous filament, and the cutting blade 131 is initially positioned at a position avoiding the two continuous filaments (first continuous filament 201 and second continuous filament 202), i.e. the first continuous filament 201 and the second continuous filament 202 are respectively arranged at positions corresponding to positions where the blades 1311b and 1311a extend in directions shorter than the directions along the rotation axis 99, and further, the aforesaid symmetry plane of the cutting blade 131 coincides with the first continuous filament 201 and the second continuous filament 202. When the cutter is rotated clockwise, the extended length of the blade 1311a corresponding to the second continuous wire 202 is reduced, the second continuous wire 202 is not cut, the extended length of the blade 1311b corresponding to the first continuous wire 201 is increased, and the first continuous wire 201 can be cut. When the cutter is rotated counterclockwise, the extended length of the blade 1311a corresponding to the second continuous wire 202 increases, and the second continuous wire 202 can be cut, and the extended length of the blade 1311b corresponding to the first continuous wire 201 decreases, and the first continuous wire 201 is not cut. In fig. 15a, when the cutter continuously rotates a large angle clockwise or anticlockwise, the two continuous filaments can be cut off successively. Compact structure, reliable operation, quick response and convenient arrangement.

Cutting device example 9:

the cutting device of this embodiment is substantially identical to cutting device embodiment 8, except that in this embodiment the blade extension at the junction of the two blades is minimal in fig. 16a and 16 b.

As shown in fig. 16a, initially the cutter 131 is in a position avoiding two continuous filaments, and further the aforesaid symmetry plane of the cutter may coincide with the symmetry planes of the continuous filaments 201 and 202. When the cutter is rotated clockwise, the extended length of the blade 1311a corresponding to the second continuous wire 202 increases, and the second continuous wire 202 can be cut, and the extended length of the blade 1311b corresponding to the first continuous wire 201 decreases, and the first continuous wire 201 is not cut. When the cutter 131 rotates counterclockwise, the extended length of the blade 1311a corresponding to the first continuous filament 202 decreases, the second continuous filament 202 is not cut, and the extended length of the blade 1311b corresponding to the first continuous filament 201 increases, and the first continuous filament 201 can be cut. Compact structure, reliable operation, quick response and convenient arrangement.

A 3D printhead comprising a tube 50 and the cutting device of any of embodiments 1 to 9, the tube 50 being adapted to convey the cut material, the tube 50 being provided with a gap for exposing the continuous filament, the blade 1311 being rotatable with the cutting blade 131 and being adapted to cut the continuous filament at the gap. More specifically:

3D printhead example 1:

a 3D printhead includes a feed tube 50 and a cutting device. Wherein the cutting device may be the cutting device of any one of embodiments 1-6. Further, the axis of the tube 50 is substantially parallel to the rotational axis 99 of the output shaft 89, and further, the distance therebetween is kept constant or the positional relationship of both the tube 50 and the driver 80 is kept constant. The tube 50 may carry the continuous filament 20, for example, the continuous filament 20 may move downwardly along arrow 98. In addition, in this embodiment, a lower pipe 501 may be further provided, and a gap is provided between the lower pipe 501 and the material pipe 50, so as to form a gap for exposing the continuous filament 20, and the continuous filament 20 is fed down into the lower pipe 501 and then further conveyed, and further, an upper port of the lower pipe 501 is coaxial with a lower port of the material pipe 50. Of course, it will be appreciated that in other embodiments, the material pipe 50 and the lower pipe 501 may be one piece, and a gap is formed at a gap corresponding to the cutter 131 to form a gap for exposing the continuous filament 20, so that the continuous filament 20 is exposed there, and the cutter 131 may be inserted, so that the cutter 131 cuts the continuous filament 20.

3D printhead example 2:

The 3D printhead of this embodiment, based on 3D printhead embodiment 1, further, as shown in fig. 7 a-7 b, the bottom end of the tube 50 is provided with an inclined nozzle 123, the second extrusion port 1202 is disposed on the inclined nozzle 123, the inclined nozzle 123 is fixedly connected to the second heating block 14-2, for example, the inclined nozzle 123 can be locked to the heating block 14-2 by a screw 68, and the 3D printhead further comprises an elbow 26 inserted into the heating block 14-2 and capable of being inserted into the inclined nozzle 123, the elbow 26 is fixed by the inclined nozzle 123 and the heating block, the inclined nozzle 123 has a through hole, preferably a through hole, which may be a stepped hole shrinking toward the direction of the second extrusion port, and the axis of the second extrusion port 1202 may be parallel or coaxial with the axis of the through hole in the inclined nozzle 123 or parallel or vertically downward with the axis of the first extrusion port 1201. The second extrusion port 1202 communicates with a pipe in the elbow 26 through a through hole in the inclined nozzle portion 123, and the pipe in the elbow 26 is an elbow. Preferably, the inclined portion of the conduit is coaxial with the through-hole in the inclined nozzle portion 123, and the upper and lower vertical portions of the elbow 26 are coaxial with the conduit in the second pipe portion 128-2. Through adopting return bend 26, realized the crooked conveying intercommunication of the material pipe from second material pipe portion to second extrusion mouth, and return bend 26 simple structure easily realizes, and the inside crooked pipeline of return bend 26 easily realizes smooth inner wall and ensures continuous fiber silk material 22 conveying's smoothness, and slope nozzle seat 123 can not need set up crooked pipeline in inside simultaneously, and the preparation is simplified, and only need the mode installation of slope can, has realized the second extrusion mouth towards first extrusion mouth interval reduce by a wide margin and can let continuous fiber silk material slope smooth extrusion. It is also preferable that the bent pipe 26 has a gap with the second pipe portion 128-2 (corresponding to the pipe 50 in the foregoing embodiment) for providing the cutter 131 of the cutter 13 to cut the continuous fiber strands 22 according to the length of the fiber strands during printing, i.e., the continuous fiber strands 20 in this embodiment are the continuous fiber strands 22. In addition, the gap effectively blocks heat conduction from the heater block 14-2 upward to the second tube portion 128-2. The heater 141-2 and the temperature sensor 142-2 may be provided in the heating block 14-2, and for example, the heating block may be made of a material having good thermal conductivity such as copper or aluminum, and the inclined nozzle portion 123 and the elbow 26 may be heated to heat the continuous fiber strand and then extrude the continuous fiber strand. Through this structure, the slope nozzle part 123 is the incline state, and the direction slope towards first extrusion opening 1201, even make first extrusion opening 1201 and second extrusion opening 1202's interval reduce by a wide margin, so can be very much do benefit to the ability of two nozzles adaptation different bend radius's printing route, also do benefit to the rotation angle who reduces nozzle seat ring 129, also do benefit to after the second extrusion opening 1202 extrudes continuous fiber silk material first extrusion opening 1201 can be more quick timely extrude the melt printing material and cladding continuous fiber silk material, more be favorable to the combination and the fusion of melt printing material and continuous fiber silk material, promote the intensity of model. In the printing process, the nozzle seat ring 129 drives the first extrusion port and the second extrusion port to rotate, the second extrusion port 1202 is kept in front, the first extrusion port 1201 is kept behind, continuous fiber silk material is obliquely extruded towards the direction of the first extrusion port 1201 when being extruded from the second extrusion port 1202, the bending angle of continuous fiber during extrusion is not 90 degrees any more, but is a smaller bending angle, the extrusion process of continuous fiber is smoother, accidental cutting, breakage or damage is avoided during extrusion of continuous fiber, and the stability of the printing process and the quality of a printed model are improved. The first tube portion 128-1 or the second tube portion 128-2 may be fixedly connected to a nozzle holder ring 129, and the nozzle holder ring 129 may be rotatably connected to the print holder 11 through a bearing 45-2. The sensor 82 may also be provided to be secured to the nozzle holder ring 129 such that the wire 85 may be passed through the through-hole 19 of the nozzle holder ring and then connected to the sensor 82, and the passive sensing element 83 may be secured to the print holder 11. A cooling fan 18 may also be provided secured to the nozzle carrier ring 129 with the air ports directed toward the freshly extruded print material of the first and second extrusion ports. Of course, the nozzle seat ring 129 is not required, and the first tube portion 128-1 or the second tube portion 128-2 or the first heating block or the second heating block may be fixedly connected to the print seat 11.

The cutter 13 is controlled in accordance with the printing process fiber arrangement instruction, and the cutter 13 may be controlled by, for example, a wire (harness) 85 passing through the through-hole 19 such that a cutter blade 131 of the cutter 13 penetrates into a gap between the elbow pipe 26 and the second material pipe portion 128-2 to cut the continuous fiber yarn 22 conveyed from the second material pipe portion 128-2 to the elbow pipe 26. Specifically, as shown in fig. 8a and 8b, fig. 8a and 8b may be regarded as bottom views of fig. 7a, 7b or 7c, and the second heating block 14-2, the second heater 141-2 and the temperature sensor 142-2 are hidden for convenience of illustration. Referring to fig. 7a, 7b, or 7c, the cutter 131 is mounted on the output shaft 89 of the server 56, and the server 56 is fixedly connected to the nozzle carrier 129, either directly or through the mounting block 127 or other components. The output shaft 89 of the servo 56 is rotatable, so that the servo 56 can drive the cutter 131 to rotate. The distance, i.e., the radius, of the outermost edge of the cutting blade 131 from the output shaft 89 is different such that when the cutting blade 131 is rotated, the distance that the cutting blade extends into the gap between the elbow 26 and the second tube portion 128-2 varies. The cutting blade 131 is located at a position where the cutting blade 131 is not in contact with the continuous fiber strands 22 at the gap between the elbow 26 and the second pipe portion 128-2 as shown in fig. 8a and 7c or 7d, and the continuous fiber strands 22 can be freely fed into the elbow 26 by the second pipe portion 128-2 and extruded by the inclined nozzle portion 123 or extruded directly from the elbow 26. When the continuous fiber strand is to be cut, the servo 56 drives the output shaft 561 to rotate, which drives the cutter 131 to rotate clockwise as shown by the arrow on the cutter 131 in fig. 8a and 7c, when the cutter 131 rotates to the position shown in fig. 8b, the area of the cutter 131 with a radius large enough reaches the gap between the elbow 26 and the second pipe portion 128-2, i.e., the cutter 131 stretches into the gap between the elbow 26 and the second pipe portion 128-2 to cut the continuous fiber strand. The cutter 131 can then be rotated in a reverse direction such that the region of greater radius exits the gap between the elbow 26 and the second conduit portion 128-2 and returns to the condition shown in fig. 8a, whereupon the continuous fiber strand can continue to the right second conduit portion 128-2 for delivery into the elbow 26. As can be seen in FIG. 7d, the second conduit portion 128-2 (i.e., conduit 50) preferably has a smaller conduit diameter than the conduit diameter of the elbow 26 corresponding to the second conduit portion 128-2 (i.e., conduit 50), and is fed into the elbow 26 from the second conduit portion 128-2 (i.e., conduit 50) for better convenience after the continuous filament 20 is severed, and a chamfer 505 is provided at the upper end of the elbow 26 to guide the introduction of the continuous filament. The first and second heater blocks 14-1 and 14-2 may be secured to the nozzle carrier ring 129 by first and second pins 27-1 and 27-1, respectively, such as by mounting blocks 127, while the cutter 56 is secured to the nozzle carrier ring. Of course, the first and second heating blocks 14-1 and 14-2 may be secured to the print head 11 by the first and second pins 27-1 and 27-1, respectively, while the cutter 56 is also secured to the print head 11.

3D printhead example 3:

the 3D printing head of this embodiment includes a tube and a cutting device, and the cutting device of this embodiment may employ the cutting device of any one of the cutting device embodiments 2 to 5 and the cutting device embodiments 7 to 9 for cutting two continuous filaments (the first continuous filament 201 and the second continuous filament 202). For the pipes in this example, as shown in fig. 3b, in some embodiments, two pipes may be provided, such as pipes 501 and 502, conveying the first continuous wire 201 and the second continuous wire 202, respectively. In other embodiments, two lines may be provided within the tube 50, as shown in fig. 4 and 14b, for conveying the first continuous strand 201 and the second continuous strand 202, respectively.

3D printhead example 4:

fig. 7d and 17 illustrate that the cutter may be positioned at the extrusion port of the nozzle 121 to cut the continuous filament 20 (for example, may be continuous filament), and the step structure 1314 may be provided on the cutter 131 so that the blade portion of the cutter may be sunk to the extrusion port of the nozzle 121, and the servo 56 and its rotation shaft, the screw 68 for fixing the cutter, etc. may be moved upwards, so that the screw 68 or the servo 56 may be prevented from being too low to affect the normal printing process of the nozzle 121. This embodiment allows the predetermined length of cut continuous filaments to be even shorter or zero. In fig. 7d, the rotation axis 99 of the cutter is shown to be substantially parallel to the axis of the continuous filament 20, the cutter 121 is in a blade type structure, and in fig. 17, the rotation axis 99 of the cutter is shown to be substantially perpendicular to the axis of the continuous filament 20, and the cutter 121 is in a ring type structure.

3D printhead example 5:

the 3D printing head of this embodiment includes a material tube and a cutting device, and the cutting device in this embodiment may be the cutting device (i.e., a cutting blade with a ring structure) in any one of embodiments 6 to 9 of the cutting device.

Further, as shown in fig. 9a, in some embodiments, a side of the lower end surface of the material pipe 50, which is close to the rotation axis in the radial direction of the rotation of the cutter (i.e., an inner annular surface of the cutter with an annular structure), is a spherical surface or a cylindrical surface that matches the cutter 131. In fig. 9a the cutter 131 is kept away from the continuous filament 20, which can be conveyed from the pipe 50 to the down pipe 501 and the nozzle 121 for extrusion, and further, the heater 141 and the temperature sensor 142 provided on the heating block 14 between the down pipe 501 and the nozzle 121 are used for heating temperature control.

In other embodiments, as shown in fig. 14a and 14b, the surface of the lower end of the tube 50 that mates with the cutter is cylindrical or spherical that mates with the outer annulus of the cutter, and the lower end of the tube 50 mates with the outer annulus of the cutter to cut. Of course, the surface of the lower end of the pipe 50 matched with the cutting knife can also be a cylindrical surface (or spherical surface) matched with the inner annular surface of the cutting knife, and the lower end surface of the pipe 50 is matched with the inner annular surface of the cutting knife to cut, similar to that shown in fig. 9a to 9 c.

In other embodiments, as shown in fig. 12a, when a cutter structure with an outer blade is used, as shown in fig. 11b, further, the upper end surface of the lower tube 501 may be a spherical surface or a cylindrical surface matching with the inner side of the cutter, and the lower end surface of the material tube 50 may be a cylindrical surface matching with the outer side of the cutter.

In other embodiments, as illustrated in fig. 12e, a cutting ring 509 may be provided on the outside of the cutter 131, with a rotatable clearance fit between the cutter and the cutting ring, the cutting ring having an inlet aperture corresponding to the tube 20 and an outlet aperture below. Fig. 12e illustrates a state in which the cutter cuts the continuous filament 20.

The blade in each of the above embodiments may have a structure with minute serrations, so-called serrated blade, and a cutting effect of faster, more regular cutting surface, or less cutting force can be achieved. Generally, in this context, it is meant that the manufacture or installation is theoretically accurate, but in practice has errors, for example, errors of less than + -45 deg., or errors of less than + -15 deg..

The continuous filament (or called wire) may be a continuous fiber, or a continuous fiber print of a continuous fiber of a prepreg, etc., and the cross section of the continuous filament may be circular or non-circular, such as polygonal, e.g. square or rectangular, etc., the length of the continuous filament is greater than the diameter of the enveloping circle of the cross section, and the length of the optimal continuous filament is greater than 10 times the diameter of the enveloping circle of the cross section. The continuous filament may be a fibrous material, a wire material (e.g., copper wire), an optical fiber material, or other continuous strand material, and may be a resin-pre-impregnated continuous fibrous material. The continuous fiber material can be carbon fiber, glass fiber, terylene, aramid fiber, ceramic fiber, boron fiber, basalt fiber, etc., or metal fiber, siC fiber, conductive polymer fiber, graphite fiber, boron fiber, silicon nitride fiber, etc. The matrix material for prepreg of the continuous fibers may be a thermoplastic resin material such as PLA (polylactic acid), PP (Polypropylen), PE (polyethylene), ABS (Acrylonitrile Butadiene Styrene), PA (Polyamide) (nylon), PC (Polycarbonate), PS (Polystyrene), PEI (Poly (etherimide)), PET (Poly (Ethylene Terephthalare)), PEEK (Polyetheretherketone), TPU (Thermoplastic polyurethanes), etc., or an epoxy resin, or a thermosetting resin material or a photosensitive polymeric resin material, or other flowable and extrudable materials, and may be a metal or a low melting point alloy, or an acrylate system shape memory polymer, a thiol-olefin system shape memory polymer.

The use of directional terms "above", "below", "left", "right" and the like are descriptive of convenience based on the particular drawings and are not to be construed as limiting the invention. In practice, the actual left or right position may be different from the figure due to the spatial transformation of the whole structure. But such variations are intended to be within the scope of the present invention. It should be noted that the above embodiments can be freely combined as needed. The foregoing is merely a preferred embodiment of the present invention and it should be noted that modifications and adaptations to those skilled in the art may be made without departing from the principles of the present invention, which are intended to be comprehended within the scope of the present invention.

Claims

1. A cutting device for cutting a continuous filament configured to be conveyed in an axial direction thereof, characterized in that the cutting device comprises a cutter rotatable about a rotation axis fixed in positional relationship with the axis of the continuous filament, the cutter having at least one blade whose position is gradually changed with respect to the rotation axis in a rotation direction of the cutter so that a distance from the blade rotated to a position corresponding to the axis of the continuous filament is gradually changed.

2. The cutting device of claim 1, wherein the blade is oriented toward the axis of rotation or the blade is oriented away from the axis of rotation; the distance from the blade edge to the axis of rotation varies gradually in the direction of rotation of the cutter.

3. The cutting device according to claim 2, wherein a distance from the rotation axis at a position of the blade corresponding to the axis of the continuous filament material uniformly varies with a rotation angle of the cutter; and/or the circumferential movement speed of the cutting knife at the position corresponding to the axis of the continuous filament is greater than the change speed of the distance from the rotation axis during the rotation of the cutting knife around the rotation axis.

4. The cutting device of claim 2, wherein:

the shape of the blade is a section of a gradual change curve;

preferably:

or, the shape of the blade is a section of a planar spiral, preferably, the starting point of the planar spiral is located on the rotation axis;

or, the shape of the cutting edge is a circle or an arc, and the center of the circle or the arc is positioned outside the rotation axis.

5. The cutting device of claim 2, wherein said cutting tool has a blade for cutting one of said continuous filaments or simultaneous cutting of a plurality of said continuous filaments; preferably, a plurality of continuous filaments are sequentially arranged along the extending direction of the cutting edge, and the normal distances between the continuous filaments and the cutting edge are equal.

6. The cutting device of claim 2, wherein said cutting tool has two said blades, each for cutting two different ones of said continuous filaments:

7. Cutting device according to claim 2, wherein the axis of rotation is parallel to the axis of the continuous filament or is arranged at an angle within ±45°.

8. The cutting device of claim 1, wherein the blades are oriented in an axial direction of the rotational axis, the blades are equidistant from the rotational axis in a rotational direction of the cutting blade, and the positions of the blades vary gradually in the axial direction of the rotational axis.

9. The cutting device of claim 8, wherein a circumferential movement speed of the blade at a position corresponding to an axis of the continuous filament is greater than a change speed in an axial direction along the axis of rotation during rotation of the cutter about the axis of rotation.

10. The cutting device of claim 8, wherein the blade is in the shape of a segment of a cylindrical helix or a segment of an edge of a cylindrical chamfer.

11. The cutting device of claim 8, wherein the blade is located on a side of the cutting blade that is closer to the axis of rotation or the blade is located on a side of the cutting blade that is farther from the axis of rotation.

12. The cutting device of claim 8, wherein said cutting tool has two said blades for cutting two said continuous filaments, respectively:

13. The cutting device of claim 8, wherein the axis of rotation is perpendicular to the axis of the continuous filament or is disposed at an angle in the range of 45 ° -135 °.

14. The cutting device of claim 1, wherein the blade is a smooth continuous blade or a serrated blade;

preferably, the serrated height of the serrated edge is smaller than the diameter of the continuous filament material and/or the envelope formed at the top or tip of the serrations of the serrated edge is a segment of a gradual curve, preferably the gradual curve comprises an involute, a spiral or an eccentric circle.

15. The cutting device of claim 1, further comprising a driver having a rotatable output shaft coupled to the cutting blade to rotate the cutting blade; preferably, the drive comprises a servo, a stepper motor or a servo motor.

16. A 3D printhead comprising a tube for transporting the continuous filament, the tube being provided with a gap for exposing the continuous filament, and a cutting device according to any one of claims 1 to 15, the blade being rotatable with the cutter and cutting the continuous filament at the gap.

17. The 3D printhead of claim 16, wherein:

18. The 3D printhead of claim 17, wherein when the blade is oriented toward the axis of rotation or the blade is oriented away from the axis of rotation; in the rotation direction of the cutter, when the distance from the cutting edge to the rotation axis is gradually changed:

19. The 3D printhead of claim 17, wherein when the blade is oriented in an axial direction of the rotational axis, the distance of the blade from the rotational axis is equal along a rotational direction of the cutter, and the position of the blade is gradually changed in the axial direction of the rotational axis:

20. The 3D printhead of claim 19, wherein the feed tube is provided with a cutting ring at the gap, the cutting ring side wall is provided with an inlet aperture or an outlet aperture corresponding to the feed tube, the cutting knife is provided in the cutting ring and is in rotatable clearance fit with the cutting ring, the inner side surface of the cutting ring at the inlet aperture or the outlet aperture forms the first feed tube end surface, or the inner side surface of the cutting ring at the inlet aperture or the outlet aperture forms the second feed tube end surface.