JP6454814B1 - Head module for 3D printer, 3D printer and modeling method - Google Patents

Abstract

Even when a modeling material has a melting temperature of 300 ° C. or higher, a temperature rise is suppressed at a supply port of a modeling material supply unit so that the modeling material does not soften. A heating head that heats a modeling material 92a that flows in the discharge head 1 and a modeling for supplying a modeling material 91 to a discharge unit 12 that is directly or indirectly connected to the discharge head 1. A heat conduction suppressing member (barrel 61, heat insulating spacer 3) having material supply holes 61a and 3a is provided, and the heat conduction suppressing member (barrel 61, heat insulating spacer 3) is 5 W / (m · ° C.) or less, preferably It is made of a material having a thermal conductivity of 3 W / (m · ° C.) or less. [Selection] Figure 1A

Description

  The present invention relates to a head module for a 3D printer, a three-dimensional (3D) printer equipped with the head module, and a modeling method.

  In recent years, manufacturing a three-dimensional model using a computer with a three-dimensional printer has been actively performed. As a device for discharging such a modeling material, for example, a device having a structure as shown in FIG. 6 is known. That is, in FIG. 6, the nozzle 81 is screwed into one end side of the heater block 83, the barrel 82 is screwed into the other end side, and a wire-shaped or rod-shaped modeling material is inserted into the barrel 82. Then, the modeling material is fed at a constant rate by the barrel 82, the modeling material is heated and melted by the heat of the heater block 83, and the molten modeling material is discharged from the discharge portion 81 a at the tip of the nozzle 81 by a certain amount. The A three-dimensional desired shaped article is manufactured by moving the position of the discharge unit 81a relative to a shaping table (not shown) that forms the shaped article in the xyz direction.

  On the other hand, Patent Document 1 discloses an ejection head capable of quick start. That is, as shown in a side view in FIG. 5, as a cheap discharge head that melts and discharges a modeling material with a small amount of heat, the flow path structure 10 is formed by, for example, a plate or a metal block, and the flow path A heating head 20 is provided on one wall surface of the structure body 10 so that a heating resistor is formed on the ceramic substrate so that it can be energized, and a mounting plate 85 provided on the opposite side of the flow path structure body 10 from the discharge portion 12. A feed mechanism (not shown) is attached to the outer periphery of the barrel 82 so that the barrel 82 is fixed to the barrel 82 and the modeling material 91 is fed at a constant pitch. The mounting plate 85 and the barrel 82 are made of metal such as aluminum or stainless steel. Therefore, a tube 82a made of a fluorine-based resin is inserted on the inner surface of the barrel 82 so that the modeling material does not adhere to the barrel 82 and the modeling material 91 moves smoothly in the barrel 82. . Although the tube is inserted also in the example of FIG. 6, it is abbreviate | omitted in the figure.

Japanese Patent No. 6154055

  As described above, the mounting plate 85 connected to the flow path structure 10 and the barrel 82 connected to the mounting plate 85 are formed of metal. Therefore, the heat of the heater block 83 shown in FIG. 6 and the heating head 20 shown in FIG. Especially recently, various materials that can be melted at high temperatures, such as materials that can withstand high temperatures, and materials that can be made stronger by adding additives to make them stronger and durable. Tends to be used. As a result, even when a modeling material is manufactured by melting the modeling material, it is necessary to be able to melt (soften so that the modeling material can be discharged) at a high temperature of 300 ° C. or higher immediately after the switch is turned on.

  When the modeling material becomes a material that melts at a high temperature in this way, the temperature of the flow path structure that causes the molten modeling material to flow also becomes very high. As a result, the heat which heated the flow-path structure 10 is conducted to the barrel 82 side which is a supply part of modeling material. When heat is transmitted to the barrel 82 side which is the modeling material supply unit, the temperature of the modeling material 91 to be supplied rises, and even if it does not reach the molten state, it softens and can be sent to the flow path structure 10 in small amounts. Disappear. As shown in Patent Document 1 described above, even if a heat insulating spacer is inserted, there is a possibility that heat conduction cannot be sufficiently prevented with porous glass or porous ceramics. The conventional modeling material supply unit (barrel 82) is formed of a metal material such as stainless steel, aluminum, titanium, or the like because of ease of processing. Therefore, even if the heat insulating spacer is inserted, the heat that has passed over the heat insulating spacer is immediately conducted through the mounting plate 85, and the temperature rises to the barrel 82 that is the supply port for the modeling material. As a result, as described above, there is a problem that the modeling material 91 to be fed into the flow channel structure 10 is softened and cannot be fed in an accurate amount. In the conventional structure shown in FIG. 6, fins are attached to the outer periphery of the barrel 82 and cooled by air cooling or the like.

  As described above, when heat is conducted to the modeling material supply unit side, not only has the problem that the feeding of the modeling material cannot be sufficiently controlled, but also the heat for heating the channel structure is sufficient. There is also a problem that heating is wasted without being supplied. In particular, this problem is more pronounced as the melting temperature of the modeling material becomes higher, for example, 300 ° C. or higher.

  The present invention has been made in view of such a situation. Even when the modeling material has a melting temperature of 300 ° C. or higher (a temperature at which the modeling material can be softened to the extent that it can be discharged), the modeling material is supplied at the supply port of the modeling material supply unit. Provided is a heat conduction suppressing member used for a discharge head that prevents the temperature from rising to a temperature at which the material softens and can use the heat for melting the modeling material in the flow path structure (discharge head) without waste. For the purpose.

  Another object of the present invention is to provide a 3D printer head module, 3D printer, and modeling method that can perform modeling using a high melting point modeling material without forcibly cooling a barrel.

  The heat conduction suppressing member of one embodiment of the present invention is directly or indirectly connected to a discharge head that discharges a modeling material, and has a modeling material supply hole for supplying the modeling material to the discharge head. It is a conduction suppression member, Comprising: The material of the said heat conduction suppression member is formed with the material whose heat conductivity is 5 W / (m * degreeC) or less.

  A head module for a 3D printer according to another embodiment of the present invention is directly or indirectly connected to a discharge head that discharges a modeling material, a heating head that heats the discharge head, and the discharge head, A heat conduction suppressing member having a modeling material conduction hole for supplying a modeling material to the discharge head, and the heat conduction suppressing member is formed of a material having a thermal conductivity of 5 W / (m · ° C.) or less. ing.

  The method for modeling a three-dimensional object according to the present invention is a method for forming a three-dimensional object, and includes forming a three-dimensional object using the 3D printer head module and a modeling material that softens at a high temperature of 300 ° C. or higher. .

A 3D printer head module according to another embodiment of the present invention includes a discharge head having a discharge port for discharging a heated and melted modeling material, and is attached to the outer surface of the discharge head and supplied into the discharge head. A modeling material supply port for supplying the modeling material to the discharge head, which is directly or indirectly connected to the heating head for heating the modeling material and the discharge head, and communicates with the discharge port. a tubular member having a supply port, and a cover which is mounted surrounding the entire circumference of the discharge head to cover the heating head adapted to protrude said discharge port, the discharge head and the cover is , Ri Do material having a high thermal conductivity than the cylindrical member, the upper inner wall of the cover is characterized that you have contact with the upper outer wall of the discharge head.

Wherein In another embodiment the head module 3D printer of the present invention, be between the cover and the discharge port, attached to the lower end of the cover, the dissipation of heat conducted from the cover A heat dissipating member is provided.

In the 3D printer head module according to another embodiment of the present invention, the cylindrical member is made of machinable ceramics, engineering ceramics, glass, titanium alloy, machinable ceramics, engineering ceramics, or glass. It is a composite material in which a tube is covered with a metal outer tube.

  Furthermore, the 3D printer of the present invention includes the 3D printer head module.

  In addition, the method for modeling a three-dimensional object according to the present invention includes forming the three-dimensional object using the 3D printer head module and a modeling material that softens at a high temperature of 300 ° C. or higher.

  According to the heat conduction suppressing member of the present invention, the heat conduction suppressing member having the modeling material supply hole for supplying the modeling material to the discharge head for discharging the modeling material, and having a thermal conductivity of 5 W / (m · ° C) The following materials are connected directly or indirectly. Therefore, it is difficult for the heat of the heated portion of the discharge head to be conducted to the modeling material supply side. As a result, even if the modeling material is a material that melts at a high temperature of 300 ° C. or higher and the temperature of the discharge head rises to 300 ° C. or higher, the heat is not easily transmitted to the modeling material supply side. As a result, the modeling material is not softened when the filament, which is the modeling material, is fed, and it becomes difficult to feed the filament. Furthermore, since the escape of the amount of heat to be heated in the flow path portion of the discharge head is reduced, the amount of heat to be heated can be used effectively, and useless heating can be suppressed.

  According to the 3D printer head module of the present invention, the discharge head and its cover member are formed of a material having a higher thermal conductivity than the heat conduction suppression member that supplies the modeling material to the discharge head. Since the heat that heats the discharge head can be effectively confined, the heat generated by the heating head can be effectively used by heating the modeling material. In addition, the heat conduction suppressing member is lower in heat than the discharge head and its cover member. Since it is set as a conductivity material, it can reduce that it conducts to the heat conduction suppression member side which supplies modeling material. As a result, even if the modeling material is a material that melts at a high temperature of 300 ° C. or higher and the temperature of the discharge head rises to 300 ° C. or higher, the heat is not easily transferred to the modeling material supply side. Even if the suppression member) is not forcibly cooled, the modeling material is not softened when the filament, which is the modeling material, is fed, and it becomes difficult to feed the filament. Furthermore, when the heat radiating member is attached to the lower end portion of the cover member, the cover member can effectively release the heat from the heating head to the heat radiating member, and the heat dissipated from the heat radiating member is tried to be laminated from now on. It can be used for heating the surface of an already-stacked shaped object, and even if it is a modeling material of a high melting point material such as PEEK, lamination (modeling) can be performed in a strong bond.

It is sectional explanatory drawing of the head module for 3D printers using the heat conduction suppression member of one Embodiment of this invention. It is an example of the plate-shaped body which comprises the discharge head used for the head module of FIG. 1A. It is a plane explanatory view in the state where the cover member of the heating head of Drawing 1A was removed. It is a side view of the state where the cover member was attached to Drawing 2A. It is a bottom view which shows the back surface of the heating head of FIG. 2A. It is a modification of the head module of FIG. 1A. It is (A) cross-section explanatory drawing of the 3D printer head module of another embodiment of this invention, and (B) bottom explanatory drawing. It is a side view which shows an example of the conventional discharge head module. It is sectional drawing which shows the other example of the conventional discharge head module.

  Next, a 3D printer head module according to an embodiment of the present invention and a heat conduction suppressing member used in the discharge head module will be described with reference to the drawings. A head module 100 for a 3D printer according to an embodiment of the present invention includes a discharge section 12 that discharges a modeling material and a flow path 11 that flows a molten modeling material, as shown in FIG. 1A. The head 1, the heating head 2 that heats the modeling material 92 a that flows in the ejection head 1, and the modeling for supplying the modeling material 91 to the ejection head 1 directly or indirectly connected to the ejection head 1. And a heat conduction suppressing member (barrel 61, heat insulating spacer 3) having material supply holes 61a and 3a, and the heat conduction suppressing member (barrel 61 and / or heat insulating spacer 3) is 5 W / (m · ° C.). Hereinafter, it is preferably formed of a material having a thermal conductivity of 3 W / (m · ° C.) or less.

  That is, in the example shown in FIG. 1A, the flow path 11 is formed so that the modeling material 92a melted (softened) in the discharge head 1 can flow, and is connected to the flow path 11 for modeling. A barrel 61 of the modeling material supply unit 6 for feeding the material 91 is connected via the mounting plate 5. The barrel 61 is provided with a feeding mechanism for feeding the filament 91, which is a modeling material, at a constant pitch, and the modeling material supply unit 6 is configured, but is omitted in the drawing. A through hole (modeling material supply hole) 61 a for supplying the filament 91, which is a modeling material, to the flow path 11 is formed at the center of the barrel 61. In the embodiment shown in FIG. 1A, although not essential, the heat insulating spacer 3 is inserted between the ejection head 1 and the mounting plate 5. The heat insulating spacer 3 also has a through hole (modeling material supply hole) 3a for supplying a filament 91, which is a modeling material, to the discharge head 1 at the center thereof. As a result, as shown in FIG. 1A, a flow passage for the modeling material that communicates from the barrel 61 to the discharge portion 12 of the discharge head 1 is formed. The barrel 61 and the heat insulating spacer 3 are formed by the above-described heat conduction suppressing member. Use of this heat conduction suppression member does not need to be used for both the barrel 61 and the heat insulating spacer 3, and may be used for only one of them or in other configurations.

  In recent years, in order to form leads and the like, it is required to discharge and form an alloy material as a conductive material, or because of a demand for a molded article with high strength, a metal powder or metal oxide is added to a molding material made of resin, etc. A modeling material in which a filler having a high melting point or the like is mixed is required, or various sensor functional materials are required. As a result, the present inventor, as described above, even with a molding material having a high melting point of about 300 ° C., immediately after the switch is turned on, the temperature is immediately raised to melt and a quick start can be performed. However, when the modeling material is heated to about 300 ° C., the modeling material supply unit 6 also has a problem that the temperature rises.

  As described above, when the melting temperature of the modeling material reaches 300 ° C. or higher, the temperature of the barrel 61 that is the supply portion of the modeling material 91 rises, and the modeling material (filament) 91 may not be fed smoothly. obtain. Thus, as a result of extensive studies by the present inventor, it was considered to suppress heat conduction from the discharge head 1 to the modeling material supply unit 6. That is, in the conventional ejection head, the barrel 82 and the attachment portion 85 (heater block 83) shown in FIGS. 6 and 5 are formed of a metal such as aluminum or stainless steel in order to facilitate the attachment structure. Therefore, the heat of the heater block 83 of FIG. 6 and the heating head 20 of FIG. 5 is easily conducted to the barrel 82 side, and the temperature of the barrel 82 is likely to rise. Therefore, by controlling the heat conduction to at least about 1/3 or less, preferably about 1/5 or less, more preferably about 1/10 or less, a modeling material (filament) in the barrel 61 (see FIG. 1A). It has been found that the temperature rise of the barrel 61 can be suppressed to such an extent that the softening of 91 can be suppressed.

  As an example, the barrel 61 has a length of about 25 to 35 mm and is fitted into the mounting plate 5 with a screw having a diameter of φ6 mm, and a modeling material supply hole 61 a having an inner diameter of φ2 mm is formed at the center. In the conventional structure, a cylindrical ring-shaped tube 82a (see FIG. 5) is inserted with the through hole having a diameter of about 3.2 mm. However, in this embodiment, an engineering ceramic such as machinable ceramic or zirconia described later is used. Since it is used, this tube is unnecessary.

  This suppression of heat conduction can be achieved by inserting a heat conduction suppression member between the modeling material supply port and the ejection head 1. Specifically, the barrel 61 is formed of a heat conduction suppression member. Or by inserting a heat insulating spacer 3 between the ejection head 1 and the mounting plate 5 and forming the heat insulating spacer 3 with a heat conduction suppressing member.

  The heat conduction suppressing member can be obtained by using a material having a low heat conductivity. As described above, Al and stainless steel are used as materials for the conventional mounting portion 85 and barrel 82 (see FIG. 5), but the thermal conductivity of Al is 230 W / (m · ° C.), and stainless steel is used. The thermal conductivity of steel is 16.3 to 27.2 W / (m · ° C.). Therefore, it is preferable to make the thermal conductivity about 1/5 or less of these, specifically, 5 W / (m · ° C.) or less is preferable, and more preferably 3 W / (m · ° C.) or less is used. Can be achieved.

  Examples of solid materials having low thermal conductivity include machinable glass ceramics (for example, Macor (registered trademark): thermal conductivity of 1.4 W / (m · ° C.)) manufactured by Corning, and engineering ceramics (for example, zirconia: thermal conductivity). Glass (for example, borosilicate glass, quartz glass: thermal conductivity 1.4 W / (m · ° C.)) or the like can be used.

  Among the materials described above, machinable ceramics are particularly preferable because they have a thermal conductivity of about 1.4 W / (m · ° C.), which is 1/10 or less that of stainless steel and can be easily processed. In addition, since this material is ceramic, even if the filament 91 partially melts in the modeling material supply holes 61a and 3a, the molten modeling material 92a is difficult to adhere, so the modeling material supply hole 61a. There is no fear of deposits in 3a. That is, in the barrel 82 made of a conventional metal material, as shown in FIG. 5, it is necessary to insert a tube 82a made of a fluororesin into the inside thereof. However, in this embodiment, this is not necessary. When forming the barrel 61 with this machinable glass ceramic, as shown in FIG. 1A, it can be attached by cutting a screw at one end and screwing it into the attachment plate 5, or in a fitting hole formed in the attachment plate 5. It is also possible to insert the barrel 61 and fix it with screws from the outside of the mounting plate 5.

  In the example shown in FIG. 1A, this heat conduction suppressing member is formed on the barrel 61. The barrel 61 has a through-hole formed at the center thereof, and a modeling material supply hole 61a is formed. The modeling material supply hole 61 a is formed so as to be connected to the flow path 11 of the ejection head 1. Since the barrel 61 is formed of a heat conduction suppressing member, for example, even if heat is transmitted to the end portion of the barrel 61 on the discharge head 1 side, the heat is transmitted to the opposite side of the barrel 61 from the discharge head 1. It is suppressed and the temperature rise of the whole barrel is suppressed. As a result, the filament 91, which is a modeling material, is not softened at the entrance of the barrel 61, and the filament 91 can be smoothly fed.

  In the embodiment shown in FIG. 1A, the heat insulating spacer 3 is inserted between the ejection head (flow channel structure) 1 and the mounting plate 5, and the heat insulating spacer 3 is also formed of the above-described heat conduction suppressing member. Since the heat insulating spacer 3 is provided between the ejection head 1 and the mounting plate 5, conduction of heat from the ejection head 1 having the highest temperature to the barrel 61 side is suppressed, which is most effective. . That is, not only can the heating of the barrel 61 be suppressed, but the heat of the discharge head 1 is not released, and the heat is effectively used for heating the soft modeling material 92 a in the flow path 11 inside the discharge head 1. In the example shown in FIG. 1A, both the barrel 61 and the heat insulating spacer 3 are formed of the heat conduction suppressing member, but both of them need not be formed of this material, and only one of them may be used.

  Further, the heat insulating spacer 3 itself may be omitted. If the thermal conductivity of the barrel 61 is small, even if the temperature on the discharge head 1 side rises, the temperature rise on the supply side of the filament 91 of the barrel 61 is suppressed, and the problem of softening the filament 91 is unlikely to occur. . On the other hand, a heat conduction suppressing member may be interposed in addition to these. For example, a metal material has been conventionally used as the mounting plate 5, but this mounting plate 5 may also be formed of a heat conduction suppressing member. As described above, machinable ceramics such as fluorine phlogopite, borosilicate glass, and engineering ceramics such as zirconia can be processed, so that screw holes can be easily formed. As a result, most of the heat generated in the ejection head 1 can be used for heating the ejection head 1, and the thermal efficiency is greatly improved.

  As shown in FIG. 1A, the 3D printer head module 100 according to the present embodiment includes a modeling material supply unit 6 including a mounting plate 5 and a barrel 61 in the discharge head 1, and a side surface of the flow path 11 of the discharge head 1. And a heating head 2 that heats the softened modeling material 92 a in the flow path 11.

  That is, the discharge head 1 may have a structure in which, for example, a vertical through hole serving as the flow path 11 is formed in a rod-shaped metal block, and the heating head 2 is attached to at least one wall surface of the flow path. As shown in the example shown in FIG. 1, a plate-like body 1a is formed with an elongated through-hole that matches the length of the flow path 11, and a plurality of the through-holes are stacked so that the through-holes of the plate-like body 1a overlap. By providing the heating head 2 at one end portion, the softened modeling material 92a in the flow path 11 may be heated. In the case of forming with a metal block, it is preferable that the heating head 2 is provided such that one wall surface of the flow path 11 of the metal block is thinned or the flow path 11 is exposed because heating efficiency can be improved. Further, when the plate-like body 1a is formed, as shown in FIG. 1A (in FIG. 1A, two plate-like bodies are overlapped and a sectional view taken along the center line of FIG. 1B is shown), If the heating head 2 is formed at both ends, the flow path 11 is formed and the heating head 2 may be sufficiently heated. However, the heating head 2 may be bonded only to one end. In this case, the flow path 11 is formed by closing the other end of the through hole (the other side wall of the flow path 11) with the closing plate.

  More specifically, a plate-like body 1a as shown in FIG. 1B is used. In this plate-like body 1a, for example, a through hole serving as a flow path 11 having a width L of about 2 mm is formed in a plate-like body having a thickness of about 1 mm, a width W of about 4 mm, and a length H of about 20 mm. A groove is formed as a discharge part 12 having a width M of about 0.3 mm and a depth of about 0.15 mm so that the tip part communicates with the flow path 11. This plate-like body 1a is bent at a position P where the length J from the tip of the discharge portion 12 is about 13 mm, and the end opposite to the flow path 11 (discharge portion 12) is the attachment portion 15. An attachment hole 16 is formed in the attachment portion 15 with a size of about φ2.2 mm, and is attached to the attachment plate 5 shown in FIG. In the example shown in FIG. 1A, the heat insulating spacer 3 is inserted between the mounting portion 15 and the mounting plate 5. The length K of the mounting portion 15 is formed at about 6.8 mm, of which about 1.8 mm is spent on the bent portion. Therefore, although not shown, a groove having a width of about 1.8 mm and a depth of about 0.6 mm is formed so as to be easily bent. These holes and grooves are formed by etching, but may be formed simultaneously with the formation of the outer shape by a punching die. In this case, the through hole may be formed by a mold, and the groove may be formed by etching. In this example, one flow path 11 is formed. However, when a plurality of the flow paths 11 are arranged to form a line head, the width W in FIG. It can be formed by arranging a plurality.

  Such a plate-like body 1a is joined, for example, after the two attachment portions 15 are bent in opposite directions, and then overlapped and joined so that the through holes serving as the flow paths 11 coincide. Is formed. Bonding of the plate-like body 1a is performed by brazing with a silver brazing material that can withstand a high melting point of the modeling material, for example, a high temperature of about 300 ° C. In this case, since metal plates made of, for example, stainless steel are joined together, there is no need for metallization, and a sheet-like brazing material or a ribbon-like brazing material is directly scattered and applied with a flux and stacked. It can be brazed by melting in a heating furnace. Note that brazing can be performed without flux by brazing in a vacuum furnace or a reducing atmosphere furnace. In the discharge head 1 formed in this way, the vertically long through holes formed in the plate-like body 1a serve as the flow path 11. Therefore, even if the two plate-like bodies 1a are joined, both ends of the through-holes are Since it is open, the two opposing side surfaces of the flow path 11 are open. As shown in FIG. 1A, the heating head 2 is attached to both surfaces.

  The structure of the heating head 2 shown in FIG. 1A will be described below with the structure shown in FIGS. The heating head 2 may be joined to the ejection head 1 after the ejection head 1 is formed, and the ejection head 1 and the heating head 2 may be joined. It may be attached.

  2A to 2C, the heating head 2 has a heating resistor 22 and the like formed on one surface of the insulating substrate 21, and a cover member 26 formed on the surface thereof. The exposed surface of the heating head 2 is the insulating substrate 21. Since the other surface (back surface) is flatter and the insulating substrate 21 is thicker, the temperature tends to be uniform (the temperature of the heating resistor 22 is the highest, but is affected by this). It is preferable that the other surface side of the insulating substrate 21 is set to the ejection head 1 side. With this structure, as described above, the metallization 21a can be brazed in advance on the other surface side of the insulating substrate 21.

  More specifically, the heating head 2 includes, for example, a plan view in which the cover member 26 (see FIG. 2B) of the example is removed in FIGS. 2A to 2C, a side view in which the cover member 26 is provided, and a bottom view (back surface). ) Are formed as shown. In the heating head 2, for example, as illustrated in FIGS. 2A to 2C, a heating resistor 22 that heats the insulating substrate 21 is formed on one surface of the insulating substrate 21. The heating resistor 22 is formed with electrodes 23 for flowing a current in the longitudinal direction connected to both ends of the heating resistor 22, and the end thereof is formed at the end of the insulating substrate 21. The electrode terminal 23a extends to the back surface of the insulating substrate 21 through the hole. Leading out to the back surface of the insulating substrate 21 facilitates connection of the leads 27, but it is not always necessary to do so. In the example shown in FIG. 2A, the second heating resistor 22a is further formed to have a length that is about half of the direction of the discharge portion 12 side. This is because the temperature on the discharge unit 12 side is increased to facilitate discharge, and the temperature is not increased excessively on the supply port 13 (see FIG. 1B) side of the modeling material 91. However, the arrangement and shape of the heating resistor 22 are not limited to this example, and can be formed in various shapes. In short, it is preferable that the temperature on the discharge unit 12 side is higher than that on the modeling material supply port 13 side. Further, a temperature measuring resistor 24 is formed in the vicinity of the heating resistor 22.

  A temperature measuring terminal 25a is formed on the temperature measuring resistor 24 via a temperature measuring wiring 25 for measuring the electrical resistance at a predetermined location, for example, at both ends and an intermediate portion thereof. The temperature measuring terminal 25a is also led out to the back surface of the insulating substrate 21 through the through hole of the insulating substrate 21, like the electrode terminal 23a. The materials such as the heating resistor 22 and the temperature measuring resistor 24, the formation method, and the like are the same as those described in the above-mentioned Japanese Patent No. 5987979 and formed by the same method. A cover member 26 (see FIG. 2B) is formed on these by a glass material or a ceramic substrate, and the surface of the heating resistor 22 and the like is protected. Further, as shown in FIG. 2C, the electrode terminal 23a of the heat generating resistor 22 and the temperature measuring terminal 25a of the temperature measuring resistor 24 are connected to lead on the back side of the ceramic substrate 21 via the wirings 23b and 25b. 27. The wires 23b and 25b are not provided, and the lead 27 may be directly connected to the electrode terminal 23a or the temperature measuring terminal 25a.

  The lead 27 is connected to the wirings 23b and 25b and the terminals 23a and 25a by an inorganic conductive adhesive having heat resistance with respect to a temperature of 300 ° C. or higher. In order to use the modeling material discharge head, a control unit including a driving circuit for the heating resistor 22 and a measurement circuit for measuring the temperature of the insulating substrate 21 can be provided. The control means controls the drive circuit by controlling the current of the heating resistor 22 so that the temperature of the insulating substrate 21 becomes a predetermined temperature. This control is also the method described in the above-mentioned Japanese Patent No. 598799. Can be done at. Although not shown, the connecting portion between the lead 27 and the electrode terminal 23a or the temperature measuring terminal 25a is protected by a protective member so that the lead 27 does not break at the connecting portion. In FIG. 2A, the lead 27 is omitted because the connecting portion is on the back side of the insulating substrate 21.

  In the present embodiment, as shown in FIG. 2C, a metallized 21 a is formed on the back surface of the insulating substrate 21 of the heating head 2. The metallized 21 a is formed in a joining region for joining with the ejection head 1. That is, the opposite side surfaces (both end surfaces of the through hole) of the flow path 11 of the discharge head 1 are exposed, and no metallization is formed on the exposed portion of the flow path 11. Even if metallization is formed in this portion, there is no problem, but the material is wasted. Since the discharge part 12 becomes thinner than the flow path 11 at the end part on the discharge part 12 side, a part of the side surface of the discharge head 1 remains, so the flow path 11 is not exposed. Therefore, the metallized 21a is formed on the insulating substrate 21 so that the part can be brazed, and the part of the metallized 21a is U-shaped. In addition, since the heating head 2 is provided on the side opposite to the discharge part 12 side by being attached to the attachment part 15, a sealing material made of an inorganic adhesive such as ceramic, glass or metal is applied and solidified. By doing so, the attachment part 15 and the heating head 2 are joined, and the modeling material is prevented from flowing out.

  This metallized 21a is formed by applying a material mainly composed of Ag, Pd, Pt or the like to a metallized formation place on the back surface of the insulating substrate 21 and baking it at about 600 to 800 ° C., for example. . Similarly, the heating resistor 22, the temperature measuring resistor 24, the electrode 23, and the like are formed by applying and baking a paste in which Ag, Pd, or the like is mixed. Can be formed. Forming the metallized first is preferable from the viewpoint of baking at a sufficiently high temperature and preventing the resistance value of the heating resistor 22 from fluctuating.

  A silver solder (for example, the above-mentioned JIS standard BAg-7 described above) that is formed into a sheet shape or a wire shape or a paste shape so that it can be applied between the heating head 2 having the metallized insulating substrate 21 and the discharge head 1. The brazing is carried out by heating the surface to about 700 ° C. with the silver brazing material having a main component of n. Even if such a brazing material is not used, the brazing portion of the discharge head 1 or the metallized portion of the insulating substrate 21 is subjected to silver plating, copper plating, etc., so that the temperature of the brazing material is simply raised. Thus, both metals can be alloyed and melted at about 700 ° C. for brazing.

  In the example shown in FIG. 1A, the heating heads 2 are respectively provided at both ends of the through holes formed in the direction perpendicular to the flow path 11 of the ejection head 1, but the heating head 2 may be only at one end. . In that case, a metal plate is affixed to the other end portion to form a closing plate. This is because one wall surface of the flow path is used.

  The mounting plate 5 to which the mounting portion 15 of the discharge head 1 is fixed is made of a metal plate having a thickness of about 3 to 10 mm, such as aluminum, and is attached by screws or the like using the mounting holes 16 of the plate-like body. It is done. In the example shown in FIG. 1A, a heat insulating spacer 3 is inserted therebetween. The heat insulating spacer 3 is formed of the above-described heat conduction suppressing member and has a thickness of about 5 to 10 mm. Further, the above-described barrel 61 is attached to the attachment plate 5. The attachment of the barrel 61 may be inserted into the fitting hole and fixed with screws from the side of the attachment plate 5 instead of being screwed as shown in the figure.

  FIG. 3 is a modification of the 3D printer head module 100 shown in FIG. 1A. The 3D printer head module 101 shown in FIG. 3 surrounds the ejection head 1 and the heating head 2 with a metal plate having a good thermal conductivity such as copper having a thickness of about 0.2 to 0.5 mm, for example, a stainless steel plate. A cover 4 is formed as described above. Therefore, if the outer shape of the head module is rectangular, the outer shape of the cover 4 is also formed in a rectangular shape. If the outer shape of the head module is circular, the outer shape of the cover 4 is also circular. The cover 4 is fixed by screwing the end of the bottom side to the mounting plate 5 or by fitting with a spring property. The end opposite to the end attached to the attachment plate 5 extends so as to cover the periphery of the discharge unit 12, but is not in contact with the discharge head 1 or the heating head 2.

  The cover 4 serves to return the heat conducted to the mounting plate 5 side to the discharge unit 12 side, and is used for heating the discharge head 1 so as not to let the heat generated from the heating head 2 escape to the outside as much as possible. Is. That is, since the cover 4 has good heat conduction as described above, the heat escaped to the mounting plate 5 can be returned to the discharge unit 12 side and the entire temperature around the heating head 2 can be maintained. .

  Moreover, the modeling method of the three-dimensional model | molding object of this invention includes forming the 3D printer head module as shown in FIG. 1, and forming a three-dimensional model | molding object using the module.

  Next, another embodiment of the 3D printer module (hot end) of the present invention will be described. FIG. 4 shows a 3D printer module according to another embodiment of the present invention. The 3D printer module includes a nozzle (discharge head) 111 having a discharge portion in which a discharge port 111a for discharging the melted modeling material is formed at the lower end (lower side of the drawing) and a melting portion for melting the modeling material, and an upper end ( A barrel (heat conduction suppressing member) 112 having a supply portion in which a supply port 112a of a filament (linear shaped material) is formed on the upper side of the drawing), and a pair of heating heads 113 as heating means for the melting portion of the nozzle 111; A cover (cover member) 115 formed so as to be in contact with and surrounding the nozzle 111, and a heat radiating plate (heat radiating member) 114 formed in contact with the cover 115 so as to surround the discharge portion of the nozzle 111. ing. In the 3D printer module, a passage 117 that communicates the supply port 112a and the discharge port 111a in a straight line is formed inside the nozzle 111 and the barrel 112.

  The barrel 112 has a double structure of a cylindrical outer tube 1121 and an inner tube 1122, and the filament supplied from the supply port 112 a formed at the upper end of the outer tube 1121 serving as a supply unit is supplied to the nozzle 111. A guide passage 117 is formed. The lower part of the outer tube 1121 is screwed into the upper part of the nozzle 111.

  A pair of slit-like (vertically long) openings 1121a are formed in the middle portion of the outer tube 1121 so as to face each other. Also, the inner diameter of the outer tube 1121 is formed to have a relatively large passage diameter upward from the lower end opening, and has a relatively small passage diameter constituting the supply port 112a at the upper end portion. The material of the outer tube 1121 is preferably a high strength material such as metal. For example, SUS, aluminum, aluminum alloy, brass, iron, nickel, titanium, or the like can be used. Note that the inner tube 1122 and the outer tube 1121 may be fixed with, for example, an inorganic adhesive or the like. If there is a predetermined difference or more in the thermal expansion coefficient (linear expansion coefficient) of each material, one point is used. It may or may not be fixed.

  The inner tube 1122 has an outer diameter that can be inserted from the lower end opening of the outer tube 1121, and has a cylindrical shape in which a passage 117 is formed in the length direction. The material of the inner tube 1122 is preferably a material having a thermal conductivity lower than that of the outer tube 1121 in relation to the outer tube 1121. The inner tube 1122 can be formed of a material having low thermal conductivity such as titanium alloy, engineering ceramics, machinable ceramics, quartz glass, borosilicate glass, polyimide resin, etc., among which transparent or translucent Quartz glass is more preferable. By using a transparent or translucent material, the inside of the passage 117 can be visually recognized from the opening 1121a of the outer tube 1121, and the state of the filament supplied into the passage 117 can be observed.

  Since the barrel 112 has a double structure of the outer tube 1121 and the inner tube 1122 having a lower thermal conductivity than the outer tube 1121, and since the opening 1121a is provided in the outer tube 1121, the heat from the nozzle 111 Can be effectively suppressed, and the temperature in the passage 117 of the barrel 112 can be kept relatively low. In particular, the portion where the opening 1121a of the outer tube 1121 is formed functions as a heat insulating portion in which heat conduction from the nozzle 111 to the supply port 112a is suppressed. In this portion, the inner tube 1122 may have a thinner side surface and an opening in order to enhance its heat insulating function.

  In the present embodiment, the barrel 112 is a double pipe, but instead of this, a material having low thermal conductivity such as titanium alloy, engineering ceramics, machinable ceramics, quartz glass, borosilicate glass, polyimide resin, etc. Single tube. Among them, it is more preferable to use a metal having a high mechanical strength and a low thermal conductivity such as a titanium alloy (for example, 64 titanium).

  In the present embodiment, a pair of openings 1121a and 1121a are formed in the middle portion of the outer tube 1121 in the barrel 112. Instead, the entire middle portion of the outer tube 1121 is eliminated, and the inner tube The upper portion and the lower portion of 1122 may be separately covered with the upper outer tube and the lower outer tube.

  The nozzle 111 has a tapered discharge portion provided with a discharge port 111a at the tip, and a melted portion in which a pair of heating heads 113 and 113 are mounted facing the left and right direction near the discharge port 111a in the middle. Is formed. The upper portion of the nozzle 111 has a cylindrical shape that is thick to attach the barrel 112, the lower portion has a substantially prismatic cylinder shape (rectangular tube shape) that is cut from the left and right directions, and the tip portion is provided to be tapered. It has been. A portion of the nozzle 111 to which the heating heads 113 and 113 are attached is further provided with a flat portion cut out from the left and right sides, and leads (lines) 1131 are led out from the heating heads 113 and 113 attached to the flat portion. Has been.

  The nozzle 111 is made of a material (material) having a higher thermal conductivity than the barrel 112, and a metal can be used. More specifically, for example, stainless steel, brass, iron, copper, aluminum and the like can be preferably used.

  As a heating means for melting the modeling material (filament), for example, a heating head in which a heating resistor layer is formed on an insulating substrate can be used. The heating head is preferable because it is excellent in miniaturization, weight reduction, and high responsiveness. The heating head 113 attached to the flat portion of the nozzle 111 which is the melting portion in the example shown in FIG. 4 includes, for example, a rectangular plate-like alumina zirconia ceramic substrate (insulating substrate) and a band-like shape formed on the surface of the insulating substrate. A thick heating resistor and two electrodes formed eccentrically at one end along the length direction of the insulating substrate so as to be connected to both ends of the heating resistor on the surface of the insulating substrate. . The surface of the heating resistor may be coated with a protective layer (dielectric layer) such as glass containing a filler. The heating head 113 is attached so that the surface of the insulating substrate on which the heating resistor is not formed faces the flat portion of the nozzle 111.

  The heating head 113 may be divided into the length direction of the nozzle 111 (vertical direction in the drawing) and may be mounted with a plurality of heating heads, so that the heating heads can be controlled to have different temperatures or different heating / lowering patterns. It may be. Further, by adding an electrode in the middle (intermediate) of the heating resistor of the heating head 113 and pulling out another lead from this, it can be controlled separately as two heating resistors, or the two heating heads 113 can be controlled separately. , 113 may be controlled by pulling out the lead 1131 so that the heating resistors are connected in parallel, or the heating heads 113, 113 can be controlled separately. Furthermore, a plurality of heating resistors may be formed on the insulating substrate of the heating head 113 so as to be controlled in common or separately.

  The cover 115 has a bottomed cylindrical shape, the nozzle 111 is inserted through the upper opening, and the tip (discharge portion) of the nozzle 111 where the discharge port 111a is formed protrudes from the opening formed on the bottom surface. The entire side surface of the nozzle 111 is covered. As a material of the cover 115, a material having high thermal conductivity is preferable in order to confine the heat of the nozzle 111 heated by the heating head 113 and transmit the heat to the heat radiating plate 114. For example, aluminum, stainless steel and the like have good workability. Metal can be used. The cover 115 is extended to a large outer diameter portion on the upper portion of the nozzle 111 in order to conduct the heat of the nozzle 111 to the heat radiating plate 14, and is in contact with the outer diameter portion or via the high thermal conductivity material. Preferably, it is mounted in contact with at least a portion of. A heat insulating material may be filled between the cover 115 and the nozzle 111 and the heating head 113. The cover 115 is formed with a through hole for leading the lead 1131 connected to the heating head 113 to the outside of the cover 115 as necessary.

  The heat dissipating member (heat dissipating plate 114) in the 3D printer module of the present invention suppresses conduction of excess heat supplied by the heating head to the side to which the modeling material is supplied for melting the modeling material. And the function of heating the region where the melted molding material is discharged. The shape of the heat radiating member can be, for example, a plate shape or a block shape, but is not particularly limited. In the case of a plate shape, for example, a circular shape, an elliptical shape, a rectangular shape, a polygonal shape, a semicircular shape, and the like can be used. The size and shape of the heat radiating part can be appropriately determined in relation to the amount of heat radiation to the area where the modeling material is discharged, the melting (dissolution, softening) temperature of the modeling material, the modeling speed, and the like.

  In the example shown in FIG. 4, the heat radiating member (heat radiating plate 114) has a disc shape, and the tip portion (discharge portion) of the nozzle 111 is inserted into the center portion to protrude in the direction of discharging the modeling material. An opening 114a is provided. The heat radiating plate 114 is attached to the bottom surface of the cover 115 so as to surround the tip of the nozzle 111 with, for example, four screws 118.

  The shape, size, and material of the heat radiating plate 114 are appropriately determined in consideration of a desired heating temperature or the like in the region where the modeling material is discharged. The thickness dimension of the heat sink 114 can be, for example, about 0.1 to 3.0 mm, and the diameter of the heat sink 114 can be, for example, about 20 to 50 mm. The shape of the heat radiating plate 114 may be an arbitrary shape such as an elliptical shape or a polygonal shape. Further, if the moving direction during the modeling operation of the 3D printer module provided with the heat radiating plate 114 can be changed by a rotation mechanism or the like, a structure that protrudes only to a part of the periphery of the discharge port 111a may be used.

  A material having a high thermal emissivity is preferable as the material of the heat sink 114. For example, ceramics such as silicon carbide, silicon nitride, and aluminum nitride, and metals such as aluminum, copper, and stainless steel can be used. Further, in order to efficiently perform heat radiation from the heat sink 114, for example, by providing a plurality of dimples on the lower surface of the heat sink 114 or by roughening the surface, the area of the lower surface of the heat sink 114 is increased. Alternatively, blackening such as forming a graphite film on the surface of the lower surface may be performed, an oxide film may be formed, or these may be used in combination. Thus, by providing a concavo-convex portion or the like on the lower surface of the heat sink 114, there is an effect that air turbulence easily occurs between the surface of the molded object and the heat sink 114, and more effective heating of the surface of the molded object. It can be performed. Note that the lower surface of the heat sink 114 may be a smooth surface.

  A heat insulating layer may be formed on the exposed upper surface of the heat sink 114. The heat insulating layer may be a structural layer other than that formed by applying or sticking a heat insulating material having a relatively low thermal conductivity. A structural thing is formed between the upper surface of the heat sink 114 and a plate-shaped body formed by providing a plate-shaped body (heat | fever reflecting plate) through the spacer on the upper surface of the heat sink 114, for example. Insulated spaces can be mentioned. Heat radiation to the upper surface side (the 3D printer module supply port 112a side) of the heat radiating plate 114 is suppressed by the heat insulating layer, and heat radiation to the lower surface side is efficiently performed.

DESCRIPTION OF SYMBOLS 1 Discharge head 1a Plate-shaped body 2 Heating head 3 Heat insulation spacer 4 Cover 5 Mounting plate 6 Modeling material supply part 61 Barrel 11 Flow path 12 Discharge part 13 Modeling material supply port 15 Mounting part 16 Mounting hole 21 Insulating substrate 22 Heating resistor 22a Second heating resistor 23 Electrode 23a Electrode terminal 24 Temperature measuring resistor 25 Temperature measuring wiring 25a Temperature measuring terminal 26 Cover member 27 Lead 100, 101 3D printer head module 111 Discharge head (nozzle)
112 Heat conduction suppression member (barrel)
113 Heating head 114 Heat radiating member (heat radiating plate)
115 Cover member (cover)

Claims (5)

A discharge head having a discharge port for discharging the heated and melted modeling material, a heating head attached to the outer surface of the discharge head and heating the modeling material supplied into the discharge head, and the discharge head, A tubular member that is directly or indirectly connected and has a supply port that is a modeling material supply port for supplying the modeling material to the discharge head and communicates with the discharge port, and causes the discharge port to protrude. the head module 3D printer and a cover mounted surrounding the entire circumference of the discharge head to cover the heating head with,
Said discharge head and said cover is Ri Do material having a high thermal conductivity than said tubular member, for 3D printer top inner wall of the cover is characterized that you have contact with the upper outer wall of the discharge head Head module. Be between the cover and the discharge port, attached to the lower end of the cover, to claim 1, characterized in that it comprises a heat dissipating member for dissipating the heat conducted from the cover The head module for 3D printer as described. The material of the cylindrical member is machinable ceramics, engineering ceramics, glass, titanium alloy, or a composite material in which an inner tube made of machinable ceramics, engineering ceramics, or glass is covered with a metal outer tube. The head module for 3D printer according to claim 1 or 2. A 3D printer comprising the 3D printer head module according to claim 1. It is a modeling method of a three-dimensional molded item, Comprising: Forming a three-dimensional molded item using the 3D printer head module of any one of Claims 1-3, and the modeling material softened at a high temperature of 300 degreeC or more. The modeling method of the three-dimensional molded object to include.

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