KR102064663B1 - Pellet Feeder using a Flexible Spiral Impeller - Google Patents

Abstract

The present invention relates to a pellet feeding device for a 3D printer, comprising: a pellet storage container for storing pellets as a molding material; an extrusion unit for melting the pellets and discharging them through a nozzle to perform three-dimensional molding; A conveying tube providing a passage for transferring the stored pellets to the extruder, an extrusion conveying means for pushing a pellet in the pellet storage container toward the extruded portion to prevent blockage in the conveying tube, and the extrusion conveying By including a drive unit for providing power for driving the means, it is possible to solve the conventional problem of clogging in the corrugated pipe while feeding the pellets directly to the extrusion unit.

Description

Pellet Feeder using a Flexible Spiral Impeller}

The present invention relates to a pellet feeding device for a 3D printer, and more particularly to a flexible spiral impeller that allows pellets to be conveyed without clogging in a FDM (Fused Deposition Modeling) 3D printer in which pellets are directly supplied to an extrusion unit. It relates to a pellet feeder.

In general, a 3D printer is a device for manufacturing three-dimensional objects by continuously spraying materials one by one based on a three-dimensional design made by specific software. It is widely used in all fields of industry such as, building, medical, food, etc., and it is also being widely used for the purpose of producing customized products by consumers with their own style and design.

The product molding method of the 3D printer is classified into FDM method (Fused Deposition Modeling), DLP method (Digital Light Processing), SLA method (Stereo lithography Apparatus) and SLS method (Selective Laser Sintering). Among these methods, the FDM type 3D printer which melts and laminates filaments of thermoplastic material has a low production cost compared to other type 3D printers, and is popularized for experimental and industrial use.

The conventional method of supplying raw materials to FDM type 3D printers includes a method of manufacturing a filament by dissolving pellets and supplying them to an extrusion part, and directly supplying pellets, a raw material of filament, to an extrusion part.

Here, the method of manufacturing the filament by melting the pellet and supplying to the extrusion part is difficult to produce a small amount because the pellet must be melt-extruded in the form of wire through a large extruder, it is disadvantageous in terms of economics because the consumption of raw materials and power is high There are disadvantages.

Therefore, an individual or an industry that uses the 3D printer for a long time is advantageous because it is possible to reduce the cost by using a 3D printer in which the pellet is directly supplied to the extrusion unit.

In general, a 3D printer in which pellets are directly supplied to an extruder is used, and a 3D printer requires a passage between a reservoir for storing pellets and an extruded portion, and a corrugated pipe, an air compressor, a spring hose, and the like are conventionally used.

In this case, the corrugated pipe is generally used a lot, and the gravity flows down the pellets to the extrusion unit, but if the sagging occurs in the corrugated pipe, the pellets do not flow down and stays in the tube causing clogging problems.

In addition, the air compressor acts to push the pellets by increasing the initial input pressure, but the cost of the compressor is high, and there is a limit to the moisture blocking with the pellets, and in the case of the spring hose, it is proposed to solve the sagging problem in the corrugated pipe. However, the hose having a diameter enough to supply a large amount of pellets requires a special production, there is a disadvantage that it is difficult to move freely because the strength is strong.

On the other hand, in the prior art, the pellet storage unit and the extrusion unit are used in combination, but the required torque of the drive shaft motor is increased due to the weight, thereby increasing the production cost and disadvantageous in accuracy and life.

Korean Patent No. 10-1678126.

The present invention has been made in order to solve the above problems, by installing and rotating a flexible spiral impeller in the corrugated pipe used as a passage between the pellet reservoir and the extruded portion, it is possible to supply the pellet to the extrusion without clogging in the corrugated pipe It is an object to provide a pellet feeder using a flexible spiral impeller.

In addition, it is an object of the present invention to provide a pellet feeding device using a flexible spiral impeller that can minimize the contact between the pellet and the air to prevent degradation of the pellet due to moisture.

In addition, by supplying pellets directly to the extruder without clogging, it is possible to omit the filament manufacturing process using a large extruder, to reduce the waste of materials, and to increase the stability and quality of the moldings. It is an object of the present invention to provide a pellet feeder using a spiral impeller.

In order to achieve the above object, in the present invention, a pellet storage container for storing the pellets as a molding material, an extrusion unit for melting the pellets and discharge through the nozzle to perform three-dimensional molding, and stored in the storage container A conveying tube providing a passage for transferring pellets to the extruder, an extrusion conveying means for pushing a pellet in the pellet storage container toward the extruded portion to prevent blockage in the conveying tube, and the extrusion conveying means Provided is a pellet feeder using a flexible helical impeller including a drive unit for providing power for driving a car.

A funnel-shaped hopper may be further included between the pellet reservoir and the transfer tube to automatically move the pellets to the transfer tube by gravity.

In the present invention, the transfer pipe may be made of a corrugated pipe capable of stretching or compressing.

In addition, the extrusion conveying means is installed in the conveying pipe is characterized in that the spiral impeller for conveying the pellet while rotating by the drive unit.

Here, the spiral impeller may be formed of a pillar connected to the driving unit and rotating as the driving unit operates, and an impeller wing formed on an outer circumferential surface of the pillar.

In this case, the pillar is characterized by consisting of a superelastic body.

In addition, the impeller wing may be made of a superelastic body, or the rigid body and the superelastic body may be formed in a shape arranged at regular intervals.

In the present invention, the super-elastic body may be made of a rubber or Ti-Ni-based alloy having a shape recovery property by the super-elasticity.

At this time, the super-elastic body is made of a Ti-Ni-based alloy, the composition is 50.2 ~ 51.5at% Ni, the balance may be made of Ti and unavoidable impurities.

In addition, the superelastic body is made of a Ti-Ni-based alloy, the composition is 49.8-51.5 at% of Ni, and 0.1 to 1 or 2 or more of Cr, Fe, V, Al, Cu, Co, Mo. 2.0 at%, and the balance may be made of Ti and unavoidable impurities.

According to the present invention as described above, by installing a flexible spiral impeller in the corrugated pipe used as a passage between the pellet storage portion and the extruded portion, it is possible to solve the conventional problem of clogging in the corrugated pipe while supplying the pellet directly to the extrusion.

In addition, there is an effect that can minimize the contact between the pellet and the air to prevent degradation of the pellet due to moisture.

In addition, by supplying the pellet directly to the extrusion unit without clogging and used for 3D printing, it is possible to omit the filament manufacturing process using a large extruder, to reduce the waste of material and to improve the stability and quality in the production of the molding.

1 is a front view showing an embodiment of a pellet supply apparatus using a flexible spiral impeller of the present invention.
2 is a perspective view showing a transfer pipe and its internal configuration according to an embodiment of the present invention.
Figure 3 is a cross-sectional view and a cross-sectional view when bending the transfer pipe and its internal configuration according to an embodiment of the present invention.
Figure 4 is a cross-sectional view showing another embodiment of the transfer pipe of the present invention.
5 is a perspective view showing a helical impeller of the present invention.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms, and only the present embodiments are intended to complete the disclosure of the present invention and to those skilled in the art to fully understand the scope of the invention. It is provided to inform you.

1 is a front view showing an embodiment of a pellet supply apparatus using a flexible spiral impeller of the present invention, Figure 2 is a perspective view showing a transfer pipe and its internal configuration according to an embodiment of the present invention, Figure 3 Cross-sectional view and a cross-sectional view when bending the transfer pipe and its internal configuration according to an embodiment of the present invention.

As shown in FIG. 1, the pellet supply apparatus of the present invention includes a pellet storage container 10 for storing pellets as a molding material, and an extrusion part 20 for melting the pellets and discharging them through a nozzle to perform three-dimensional molding. ), A transfer pipe 30 providing a passage for transferring the pellets stored in the storage container 10 to the extrusion unit 20, and pellets in the pellet storage container 10 in the transfer pipe 30. It comprises an extrusion conveying means for pushing the toward the extrusion unit 20 to prevent clogging in the conveying pipe 30, and a drive unit 50 for providing power for driving the extrusion conveying means.

Although not shown in the drawing that the pellet is accommodated in the pellet storage container 10, pellets of various materials can be accommodated in the pellet storage container 10, the pellet storage container 10 to a plurality In addition, the pellets of various colors or various materials may be combined and printed.

A funnel-shaped hopper 12 for automatically moving the pellets from the storage container to the delivery pipe 30 by gravity is installed between the pellet storage container 10 and the delivery pipe 30.

The hopper 12 has an upper end connected to the pellet storage container 10, and a lower end connected to the transfer pipe 30 so that the pellets in the storage container 10 may be continuously introduced into the transfer pipe 30 by gravity. To help.

On the other hand, the transfer pipe 30 is provided with an extrusion transfer means for preventing the blockage phenomenon in the transfer pipe 30 by pushing the pellet in the pellet storage container 10 toward the extrusion unit (20).

In the present invention, a spiral impeller 40 is installed in the conveying pipe 30 as the extrusion conveying means and conveys the pellet while rotating by the drive unit 50.

Here, the spiral impeller 40 may be composed of a pillar 42 which is connected to the driving unit 50 and rotates as the driving unit operates, and an impeller wing 44 formed on an outer circumferential surface of the pillar 42. .

In the present invention, the drive unit 50 may be made of a drive motor, the pillar 42 of the spiral impeller 40 is axially coupled to the output shaft of the drive motor, the pillar 42 is driven as the drive motor is driven. By rotating, the impeller blades 44 are rotated to push the pellets contained in the space between the impeller blades 44, that is, the space between the impeller blades 44 toward the extruded part 20, thereby pushing the pellets into the extruded part 20. To the side.

Figure 4 is a cross-sectional view showing another embodiment of the transfer pipe of the present invention, the transfer pipe 30 may be made of a corrugated pipe that can be stretched or compressed.

Corrugated pipes are commonly used in FDM (Fused Deposition Modeling) 3D printers, which can be stretched or compressed to a certain degree, allowing flexible movements such as bending and bending flexibly, and pellets flow out into the extrusion unit 20 using gravity. Easy to make

Here, when the transfer pipe 30 is made of a corrugated pipe, the spiral impeller 40 is rotated in the state in which the edge of the impeller wing 44 is inserted into the recessed portion of the uneven surface formed on the inner surface of the corrugated pipe by a predetermined amount. It can also be configured to.

Of course, the transfer pipe 30 does not necessarily need to be a corrugated pipe, the material and diameter of the transfer pipe 30 is easy to transfer the pellets, if the flexible free movement is possible other than the pipe (tube, hose) You can also use.

On the other hand, the pillar 42 of the spiral impeller 40 may be made of a superelastic body. That is, since the pillar 42 must be capable of bending or bending together with the transfer tube 30 in the transfer tube 30 that can be flexibly and freely moved, it must be made of a material having a predetermined elastic force.

In addition, the impeller wing 44 may also be made of a superelastic body, or as shown in Figure 5, the rigid body 44a and the superelastic body 44b may be formed in a form arranged at regular intervals. As such, when the rigid body 44a and the superelastic body 44b are arranged at regular intervals, when the transfer pipe 30 is bent, the superelastic body 44b of the impeller blade 44 may move the transfer pipe 30. It can be deformed accordingly and bent in any direction to provide stable pellet supply.

In the present invention, the superelastic body constituting the pillar 42, the impeller blades 44 may be made of rubber or a Ti-Ni-based alloy as a material having shape recoverability by superelasticity.

As a superelastic material, when Ti-Ni type alloy is used, since it is excellent in the point of fatigue strength and corrosion resistance, it is preferable. In this case, alloy composition can cover a wide transformation temperature in the range of about -100-30 degreeC by making Ni 50.2-51.5at% and remainder Ti and an unavoidable impurity. In the above Ni composition range, it is known that the transformation temperature decreases by about 10 ° C each time the Ni composition ratio is increased by 0.1%.

In addition, the superelastic body is made of a Ti-Ni-based alloy, the composition is 49.8-51.5 at% of Ni, and 0.1 to 1 or 2 or more of Cr, Fe, V, Al, Cu, Co, Mo. 2.0 at%, and the balance may be made of Ti and unavoidable impurities.

The alloy composition contains 49.8 to 51.5 at% of Ni, and 0.1 to 2.0 at% of Cr, Fe, V, Al, Cu, Co, Mo, and 0.1 to 2.0 at%, and the balance is Ti and inevitable impurities. The transformation temperature can be controlled by selecting the type and amount of the minor addition element such as these.

The rights of the present invention are not limited to the embodiments described above, but are defined by the claims, and those skilled in the art can make various modifications and adaptations within the scope of the claims. It is self-evident.

10: pellet container 12: hopper
20: extrusion part 30: transfer pipe
40: spiral impeller 42: pillar
44: impeller wing 50: drive unit

Claims (11)

A pellet storage container for storing pellets as a molding material;
An extrusion unit for melting the pellets and discharging them through a nozzle to perform three-dimensional molding;
A transfer tube providing a passage for transferring the pellets stored in the storage container to the extrusion unit;
Extrusion conveying means for pushing the pellets in the pellet storage container toward the extrusion part in the conveying pipe to prevent blockage in the conveying pipe; And
A drive unit for providing power for driving the extrusion transport means;
Including;
The transfer pipe is made of a corrugated pipe capable of stretching or compressing,
The extrusion conveying means is a spiral impeller consisting of a column made of a superelastic body connected to the drive unit and rotates as the drive unit operates, and an impeller wing formed on an outer circumferential surface of the column,
The impeller wing is made of a superelastic body, or the rigid body and the superelastic body is formed in a shape arranged at regular intervals, in the state in which the edge of the impeller wing is inserted into the recess of the concave-convex formed on the inner surface of the corrugated pipe by a predetermined amount. Pellet supply device using a flexible spiral impeller characterized in that the spiral impeller is configured to rotate. The method according to claim 1,
And a funnel-shaped hopper for automatically moving the pellets to the transfer pipe by gravity between the pellet storage container and the transfer pipe. delete delete delete delete delete delete The method according to claim 1,
The superelastic body is a pellet supply device using a flexible spiral impeller, characterized in that made of a rubber or Ti-Ni-based alloy having a shape recovery property by the super-elasticity. The method according to claim 9,
The superelastic body is made of a Ti-Ni-based alloy, the composition is 50.2-51.5 at% of Ni, the balance of the pellet feeder using a flexible spiral impeller characterized in that consisting of Ti and inevitable impurities. The method according to claim 9,
The superelastic material is made of a Ti-Ni-based alloy, the composition is 49.8-51.5 at% of Ni, and 0.1 to 2.0 at least one or two or more of Cr, Fe, V, Al, Cu, Co, and Mo. A pellet feeding device using a flexible helical impeller containing%, the balance being made of Ti and unavoidable impurities.

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