JP6971427B1 - Laser laminated modeling equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a powder material supply unit which includes a supply channel forming member for forming a supply path for a powder material and supplies the powder material toward a planned stacking surface through the supply path, and a powder material supply section to a planned stacking surface. A laser irradiation unit that irradiates the supplied powder material with laser light, an outer cylinder portion that is arranged so as to surround the outer peripheral surface of the supply path forming member and forms a shield gas supply path between the outer peripheral surface, and a shield. By suppressing the spread of the shield gas in the laser laminated modeling apparatus provided with the shield gas supply unit that supplies the shield gas so as to surround the outside of the region where the powder material is supplied on the planned stacking surface through the gas supply path. , Improves the shielding property of the outside air by the shielding gas and the straight-line guidance property of the powder material. SOLUTION: A shield gas supply path 24a inside the outer cylinder portion 24 in the radial direction and an outside outside in the radial direction of the outer cylinder portion 24 are connected to a tip portion of the outer cylinder portion 24 which is an end portion on a discharge side of the shield gas. A communication hole 24c that communicates with the space is formed. [Selection diagram] Fig. 1

Description

The present invention melts and solidifies the powder material by irradiating the powder material supply unit that supplies the powder material toward the planned stacking surface and the powder material supplied from the powder material supply unit to the planned stacking surface with a light beam. The present invention relates to a laser laminated molding apparatus provided with a laser irradiation unit for forming a cured layer.

In a general laser laminated molding apparatus, a powder material supply unit and a laser irradiation unit are mounted on one processing head, and the processing head is moved along a predetermined path by a moving mechanism unit while being laminated from the powder material supply unit. The powder material is supplied toward the planned surface, and the powder material is melted and solidified by irradiating the laser beam from the laser irradiation device toward the supply area of the powder material on the planned laminated surface to form a cured layer having a desired shape. do. As the configuration of the powder supply unit, for example, a configuration in which powder material is ejected from an annular powder discharge port surrounding the center of the processing head, or a plurality of powder discharge ports arranged at equal intervals around the center axis of the processing head. A configuration for injecting the powder material and a configuration for injecting the powder material from the powder discharge port arranged in the center of the processing head are adopted.

In this type of laser laminated modeling apparatus, for example, as shown in Patent Documents 1 and 2, a shield gas may be supplied so as to surround the supply portion of the powder material on the planned lamination surface. The shield gas has a role of preventing oxidation of the powder material (metal) heated and melted by the laser beam and preventing scattering of the powder material to ensure its straightness.

Japanese Unexamined Patent Publication No. 2019-055484 Japanese Unexamined Patent Publication No. 2015-196265

Here, in the laser laminated modeling apparatus shown in Patent Documents 1 and 2, after the air flow induced on the outside of the shield gas collides with the planned stacking surface, it becomes a vortex that winds up upward and causes the shield gas to be radially outward. It acts to attract. When the shield gas is attracted to the outside in the radial direction, the shield gas spreads outward in the radial direction by the time it reaches the planned stacking surface, so that the shielding property of the outside air by the shield gas and the straight-line guidance property of the powder material are lowered. Problems arise.

The present invention has been made in view of the above circumstances, and by suppressing the spread of the shield gas, it is possible to improve the shielding property of the outside air by the shield gas and the straight-line guidance property of the powder material. The purpose is to provide a modeling device.

One aspect of the present invention for solving the above problems is
A powder material supply unit that includes a supply channel forming member that forms a supply path for the powder material and supplies the powder material toward the planned stacking surface via the supply path, and a powder material supply unit that supplies the powder material to the planned stacking surface. A laser irradiation unit that melts and solidifies the powder material to form a cured layer by irradiating the powder material with a laser beam, and an outer peripheral surface that surrounds the outer peripheral surface of the supply path forming member. An outer cylinder portion that forms a shield gas supply path between the two, and a shield gas supply section that supplies the shield gas so as to surround the outside of the region where the powder material is supplied on the planned stacking surface through the shield gas supply path. It is a laser laminated molding device equipped with
The tip portion of the outer cylinder portion, which is the end portion on the discharge side of the shield gas, communicates the shield gas supply path inside the outer cylinder portion in the radial direction and the external space outside the radial direction of the outer cylinder portion. The present invention relates to a laser laminated modeling apparatus in which a communication hole is formed.

According to this laser laminated modeling apparatus, laser laminated modeling is performed by melting and solidifying the powder material supplied from the powder material supply unit to the planned stacking surface by the laser light emitted from the laser irradiation unit. In laser laminating modeling, shield gas is supplied from the shield gas supply section to the planned laminating surface via the shield gas supply path formed between the powder material supply path forming member and the outer cylinder section, and the laminating is planned. The supply point of the powder material on the surface is surrounded by the shield gas. As a result, it is possible to prevent the powder material from reacting with the outside air to reduce the melting efficiency, and it is possible to prevent the powder material from being lowered in straightness and the laminating molding accuracy from being lowered. An external air flow induced by the inertial force is generated outside the shield gas supplied by the shield gas supply unit. After colliding with the planned stacking surface, this external air flow winds up and generates a vortex. Therefore, there is a possibility that the end portion of the shield gas on the discharge tip side is attracted radially outward due to the wound vortex, and the entire shield gas spreads radially outward. On the other hand, in the present invention, since a communication hole for communicating the shield gas supply path and the external space is formed at the tip of the outer cylinder portion, the external air flow induced to the outside of the shield gas is generated. , Can be sucked into the shield gas supply path from the communication hole before developing into the vortex. Therefore, it is possible to suppress the generation of the vortex flow and, by extension, suppress the spread of the shield gas due to the vortex flow, ensure the shielding property of the outside air by the shield gas, and improve the straightness of the powder material.

The outer cylinder portion has a double cylinder structure including a first outer cylinder portion and a second outer cylinder portion that surrounds the outside of the first outer cylinder portion, and is a supply path forming member and the first outer cylinder portion. The space between the first outer cylinder portion and the second outer cylinder portion each constitutes the shield gas supply path, and the communication hole is the tip of the second outer cylinder portion. It is formed so as to communicate the shield gas supply path formed between the second outer cylinder portion and the first outer cylinder portion and the external space outside the second outer cylinder portion. It is preferable to have.

According to this configuration, by forming the outer cylinder portion with a double cylinder structure of the first outer cylinder portion and the second outer cylinder portion, the shield gas supply path can be double-formed in the radial direction. The inner shield gas supply path is composed of a space between the powder material supply path forming member and the first outer cylinder portion, and the outer shield gas supply path is the first outer cylinder portion and the second outer cylinder portion. It is composed of the space between the parts. Since the communication hole is formed in the second outer cylinder portion, the external air flow outside the second outer cylinder portion is sucked into the outer shield gas supply path from the communication hole before developing into the vortex flow. Will be. Therefore, it is possible to avoid the problem of the spread of the shield gas caused by the generation of the vortex flow described above. Further, the external air flow sucked from the communication hole flows into the outer shield gas supply path, but does not flow into the inner shield gas supply path. Therefore, it is possible to prevent air from being mixed into the shield gas in the inner shield gas supply path on the side close to the supply point of the powder material. Therefore, it is possible to reliably prevent the oxidation reaction between the air mixed in the shield gas and the powder material (metal).

A plurality of the communication holes are provided, and it is preferable that the plurality of communication holes are arranged over the entire circumference at intervals from each other in the circumferential direction of the outer cylinder portion in which the communication holes are formed.

According to this configuration, the external air flow outside the outer cylinder portion can be sucked into the shield gas supply path from a plurality of communication holes formed over the entire circumference in the circumferential direction. Therefore, it is possible to reliably prevent the spread of the shield gas due to the development of the external air flow outside the outer cylinder portion into a vortex flow.

It is preferable that the plurality of communication holes are formed in the shape of elongated holes long in the axial direction of the outer cylinder portion in which the communication holes are formed.

According to this configuration, the communication hole is formed long in the axial direction of the outer cylinder portion, that is, in the direction in which the external air flow flows when viewed from the radial direction. Therefore, the external air flow outside the outer cylinder portion can be smoothly and surely guided from the communication hole to the outer cylinder portion.

It is preferable that the plurality of communication holes are formed in the shape of elongated holes long in the circumferential direction of the outer cylinder portion in which the communication holes are formed.

According to this configuration, the distance between adjacent communication holes can be narrowed as compared with the case where each communication hole is formed as a simple circular hole. As a result, the external air flow outside the outer cylinder portion can be efficiently guided into the communication hole in the entire circumferential direction.

It is preferable that the communication hole is inclined toward the tip portion from the radial outer side to the inner side of the outer cylinder portion in which the communication hole is formed.

According to this configuration, the communication hole is inclined toward the tip portion side (that is, the shield gas discharge side) from the radial outer side to the inner side of the outer cylinder portion. Therefore, the external air flow outside the outer cylinder portion can be smoothly sucked into the shield gas supply path without countering the flow of the shield gas.

It is preferable that the shield gas supply path is also used as an optical path for laser light emitted from the laser irradiation unit toward the planned stacking surface.

According to this configuration, since the shield gas supply path is also used as the optical path for the laser beam, the entire device can be downsized as compared with the case where the optical path for the laser beam and the shield gas supply path are separately provided. can.

As described above, according to the laser laminated molding apparatus according to the present invention, the shield gas on the radial inner side of the outer cylinder portion is attached to the tip portion of the outer cylinder portion arranged so as to surround the supply path forming member of the powder material. By forming a communication hole that communicates the supply path and the external space on the outer side in the radial direction, the external air flow is introduced from the communication hole before the external air flow induced by the shield gas flow develops into a vortex. It can be sucked into the shield gas flow path to suppress the spread of the shield gas. As a result, the shielding property of the outside air by the shielding gas and the straight-line guidance property of the powder material can be improved.

It is a schematic diagram which shows the structure of the laser laminated modeling apparatus which concerns on Embodiment 1. FIG. It is an enlarged side view which shows the tip part of the irradiation housing of the laser laminated modeling apparatus which concerns on Embodiment 1. FIG. FIG. 3 is a sectional view taken along line III-III of FIG. It is explanatory drawing for demonstrating the flow of the shield gas in the laser laminated modeling apparatus of Embodiment 1. FIG. It is an enlarged sectional view of the tip part of the irradiation housing in the laser laminated modeling apparatus which concerns on modification 1. FIG. It is a figure corresponding to FIG. 2 which shows the modification 2. FIG. FIG. 2 is a diagram corresponding to FIG. 2 showing a modified example 3. FIG. 4 is a diagram corresponding to FIG. 4 showing the second embodiment. It is a schematic diagram which shows an example of the laser laminated modeling apparatus which concerns on other embodiment. It is a figure corresponding to FIG. 4 which shows the conventional example.

Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

[Embodiment 1]
As shown in FIG. 1, the laser laminated modeling apparatus 1 of the present embodiment includes a processing head 2, a moving mechanism unit 3, and a control device 40, and is controlled by the control device 40 and is controlled by the moving mechanism unit 3. Laser laminating modeling is performed while moving 2 along the planned laminating surface S. In the example of FIG. 1, the planned stacking surface S is the surface of the work W (an example of the laminated body), but the present invention is not limited to this, and for example, the surface of the already laminated hardened layer or the apparatus. It may be a base.

The moving mechanism unit 3 includes a ball screw mechanism for linearly moving the machining head 2 in the X-axis, Y-axis, and Z-axis directions, a tilt mechanism for swinging the machining head 2, and the like with respect to the work W. The three-dimensional relative position of the processing head 2 can be changed.

The processing head 2 includes a powder material supply unit 10 that supplies the powder material P to the planned stacking surface S, a laser irradiation unit 20 that irradiates the laser beam L toward the planned stacking surface S, and a shield gas that supplies the shield gas. It has a supply unit 30 and an irradiation housing 24 that forms an optical path through which the laser beam L passes and a shield gas supply path. The powder material supply unit 10, the laser irradiation unit 20, the shield gas supply unit 30, and the irradiation housing 24 are unitized via a housing or the like and are integrally driven by the moving mechanism unit 3.

The laser irradiation unit 20 includes a laser oscillator 21, a conversion optical system 22, and a condenser lens 23.

The laser oscillator 21 is an oscillator that outputs a laser beam L, and a CO ₂ laser oscillator is generally adopted, but the laser oscillator 21 is not limited to this. In the example of FIG. 1, the laser oscillator 21 is mounted on the processing head 2, but is not limited to this, and is fixed at a place different from the processing head 2 and emitted from the laser oscillator 21. The laser beam L may be guided to the processing head 2 via an optical transmission path such as an optical fiber.

The conversion optical system 22 includes an optical element that converts the laser beam L emitted from the laser oscillator 21 into annular light. As for the conversion optical system 22, for example, the well-known configuration described in Japanese Patent Application Laid-Open No. 2019-098373 can be adopted, and therefore detailed description thereof will be omitted.

The condenser lens 23 guides the laser beam L converted into an annular shape by the conversion optical system 22 to the space 24a in the irradiation housing 24 described later, and surrounds the supply point of the powder material P on the planned stacking surface S. Condensate. A supply nozzle 11, which is a part of the powder material supply unit 10 described later, penetrates the axial center portion of the condenser lens 23 in the vertical direction.

The irradiation housing 24 (an example of the outer cylinder portion) is composed of an inverted truncated cone-shaped tubular member coaxially arranged with the supply nozzle 11. The irradiation housing 24 is arranged so as to surround the supply nozzle 11 (an example of a supply path forming member), and is directed downward between the outer peripheral surface of the supply nozzle 11 and the inner peripheral surface of the irradiation housing 24. A space 24a having a small outer diameter is provided. This space 24a constitutes an optical path of the laser beam L that has passed through the condenser lens 23, and is also used as a shield gas supply path. At the lower end of the irradiation housing 24, a plurality of communication holes 24c that communicate with each other inside and outside the space 24a are formed. The details of the communication hole 24c will be described later.

Thus, according to the processing head 2, the laser light L output from the laser oscillator 21 is converted into annular light via the conversion optical system 22, and then passes through the condenser lens 23 to the irradiation housing 24. It enters the space 24a in the irradiation housing 24 from the upper end opening 24d, and is irradiated from the lower end opening 24b of the irradiation housing 24 toward the planned stacking surface S. The condenser lens 23 concentrates the laser beam L so as to be in focus at a point separated from the lower end opening 24b by a predetermined distance.

The powder material supply unit 10 has a supply nozzle 11 arranged at the axial center portion of the irradiation housing 24. The supply nozzle 11 is composed of a hollow tube extending in the vertical direction, and the hollow portion inside the supply nozzle 11 functions as a supply path 11a for the powder material P. Then, the powder material supply unit 10 applies the powder material (specifically, the metal powder) P to the region forming the cured layer on the planned stacking surface S via the supply path 11a of the supply nozzle 11 with argon or the like. It is supplied together with a carrier gas consisting of an inert gas. The laser beam L is focused by the condenser lens 23 so that the focal point is located at the convergence point of the powder material P. The metal powder supplied to the planned stacking surface S together with the carrier gas is heated and melted by the energy of the laser beam L to form a molten pool, and the molten pool is no longer irradiated with the laser beam L due to the movement of the processing head 2. By solidifying the metal, a cured layer having a desired shape is laminated (such a processing phenomenon is called "laser laminated molding").

The shield gas supply unit 30 supplies the shield gas so as to surround the supply portion of the powder material P on the planned stacking surface S. Specifically, the shield gas supply unit 30 supplies the shield gas from the upper end opening 24d of the irradiation housing 24 to the planned stacking surface S via the space 24a in the irradiation housing 24. The shield gas has a role of preventing the air outside the supply point of the powder material P from reacting with the powder material P by surrounding the supply point of the powder material P and a role of preventing the powder material P from scattering and ensuring its linearity. I am in charge. As the shield gas, for example, an inert gas such as argon or helium is generally used.

Based on the machining program storage unit 41 that stores the machining program and the machining program stored in the machining program storage unit 41, the control device 40 has a moving mechanism unit 3, a powder material supply unit 10, a laser oscillator 21, and a laser oscillator 21. It includes a control unit 42 that controls the shield gas supply unit 30.

The machining program commands the operation of the laser oscillator 21 such as ON and OFF, the operation of the moving mechanism unit 3 for controlling the position of the machining head 2, and the like by a code. By this machining program, the machining W is machined. The movement locus of the head 2 is defined.

When the control unit 42 receives a machining cycle execution command from an operation panel (not shown), the control unit 42 executes the machining program, that is, interprets the code commanded in the machining program and outputs a control signal corresponding to the code. Execute laser laminated modeling control with. In the laser laminated molding control, the moving mechanism unit 3, the powder material supply unit 10, the laser oscillator 21, and the shield gas supply unit 30 are operated to form a cured layer having a desired shape on the planned lamination surface S.

According to the laser laminated modeling apparatus 1 of the present embodiment having the above configuration, the machining program stored in the machining program storage unit 41 is executed by the control unit 42, and the laser is executed by the control unit 42 according to this machining program. The operations of the oscillator 21, the moving mechanism unit 3, the powder material supply unit 10, and the shield gas supply unit 30 are controlled, and the machining head 2 and the work W move relatively to the work W by the machining head 2. On the other hand, laser laminated modeling is executed.

That is, the laser light L output from the laser oscillator 21 is converted into annular light via the conversion optical system 22, then passed through the condenser lens 23 and introduced into the space 24a in the irradiation housing 24, and is introduced into the irradiation housing 24. The light is focused on the focal position separated from the lower end opening 24b of the 24 by a predetermined distance. Further, a shield gas is supplied from the shield gas supply unit 30 to the space 24a in the irradiation housing 24, and the shield gas is ejected from the lower end opening 24b of the irradiation housing 24.

Then, in this state, the powder material (metal powder) P for laser laminated molding is a carrier gas in the focal region of the laser beam L irradiated from the irradiation housing 24 from the powder material supply unit 10 via the supply nozzle 11. Supplied with. Thus, when the metal powder is supplied to the focal region of the laser beam L, it is heated and melted by the laser beam L and deposited on the planned stacking surface S of the work W. At that time, the metal powder heated and melted by the laser beam L is prevented from being oxidized by the shield gas, and its spread in the radial direction is suppressed to ensure straightness. The position of the irradiation housing 24 of the machining head 2 and the work W are controlled so as to move relative to each other in the three-dimensional space by the moving mechanism unit 3, and such relative movement causes the work W to move on the planned stacking surface S. A laminated model of a predetermined shape is deposited on the surface.

By the way, in the conventional laser laminated modeling apparatus, the shield gas supplied by the shield gas supply unit spreads outward in the radial direction, so that the shield gas reduces the shielding property of the outside air and the straight-line guidance property of the powder material P. There is a problem of inviting.

FIG. 10 is an explanatory diagram for explaining this problem, and schematically shows the shield gas flow g and the external air flow h in the conventional laser laminated modeling apparatus. In FIG. 10, 100 is added to the reference numerals of the components used in the present embodiment for the same components as the laser laminated modeling apparatus 1 of the present embodiment.

In the conventional laser laminated modeling apparatus, when performing laser laminated modeling, the shield gas flow g is introduced from the shield gas supply unit (not shown) into the space 124a in the irradiation housing 124, as in the present embodiment. The introduced shield gas flow g is supplied from the lower end opening 124b of the irradiation housing 124 on the planned stacking surface S so as to surround the convergent region of the powder material P. An external air flow h induced by the inertial force of the shield gas flow g is generated around the irradiation housing 124. This external air flow h flows downward along the outer wall surface of the irradiation housing 124, then slightly changes its course inward in the radial direction so as to be attracted to the shield gas flow g, and then collides with the planned stacking surface S. Then, it is wound diagonally upward on the outer side in the radial direction to form a vortex. Then, the discharged tip portion of the shield gas flow g is attracted radially outward due to this rolled-up vortex flow, and the entire shield gas flow g spreads radially outward (A direction in FIG. 10). When the shield gas flow g spreads to the outside, there arises a problem that the shielding property of the external air by the shield gas and the straight-line guidance property of the powder material P are deteriorated.

In order to avoid this problem, in the present embodiment, the communication hole 24c is formed in the irradiation housing 24. As shown in FIGS. 1 to 3, the communication hole 24c is formed at the tip end portion of the irradiation housing 24, which is the end portion on the discharge side of the shield gas. In this example, a total of six communication holes 24c are provided. The six communication holes 24c are formed radially around the axis of the irradiation housing 24 in a plan view and are arranged at equal intervals in the circumferential direction. Each communication hole 24c penetrates in the radial direction of the irradiation housing 24 so as to communicate with the space 24a (shield gas supply path) inside the irradiation housing 24 and the external space. The number of communication holes 24c is not limited to six, and may be, for example, seven or more, or five or less.

As described above, according to the laser laminated modeling apparatus 1 of the present embodiment, the communication hole 24c is formed at the tip of the irradiation housing 24, so that the communication hole 24c is induced by the shield gas flow g as shown in FIG. Before the external air flow h develops into the above-mentioned vortex flow, it is sucked into the space 24a in the irradiation housing 24 from the communication hole 24c by the negative pressure of the shield gas flow g. Therefore, it is possible to prevent the shield gas flow g from spreading outward in the radial direction due to the influence of the eddy current. As a result, the shielding property of the external air by the shield gas flow g is ensured to suppress the oxidation reaction of the powder material P, and the straight-line guidance of the powder material P by the shield gas flow g is improved to improve the shape of the laminated model. The accuracy can be improved.

Further, a plurality of communication holes 24c are provided, and the plurality of communication holes 24c are arranged so as to be spaced apart from each other in the circumferential direction of the irradiation housing 24 over the entire circumference.

According to this configuration, the external air flow h outside the irradiation housing 24 is introduced into the space 24a (inside the shield gas supply path) in the irradiation housing 24 from the plurality of communication holes 24c formed over the entire circumference in the circumferential direction. Can be inhaled. Therefore, it is possible to reliably prevent the external air flow h outside the irradiation housing 24 from developing into a vortex flow.

Further, the space 24a in the irradiation housing 24 is used not only as a shield gas supply path but also as an optical path for the laser beam L.

According to this configuration, the entire laser laminated modeling apparatus 1 can be miniaturized by using the space 24a in the irradiation housing 24 for two purposes, the shield gas supply path and the optical path of the laser beam L. can.

[Modification 1]
FIG. 5 shows a modification 1 of the first embodiment. In the first modification, the shape of the communication hole 24c is different from that of the first embodiment. In the following modifications and embodiments, the same components as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

That is, in this modification, each communication hole 24c is inclined toward the tip end side (lower side in this example) from the radial outer side to the inner side of the irradiation housing 24.

According to this configuration, the external air flow can be sucked into the communication hole 24c at a gentle angle as compared with the case where the communication hole 24c penetrates in the radial direction as in the first embodiment. Further, since the sucked air can be smoothly flowed along the flow of the shield gas, it is possible to prevent the sucked air from being mixed in the shield gas. Therefore, it is possible to prevent the mixed air from reacting with the metal powder (powder material P) to reduce the melting efficiency.

[Modification 2]
FIG. 6 shows a modification 2 of the first embodiment. In the first modification, the shape of the communication hole 24c is different from that of the first embodiment.

That is, in this modification, each communication hole 24c is formed in the shape of an elongated hole long in the axial direction of the irradiation housing 24.

According to this configuration, the communication hole 24c can be formed long in the axial direction of the irradiation housing 24, that is, in the direction in which the external air flow h flows when viewed from the radial direction. Therefore, the external air flow h flowing along the outer wall surface of the irradiation housing 24 can be smoothly and surely guided into the irradiation housing 24 from the communication hole 24c. By combining the modified example 1 and the modified example 2, the introduction of the outside airflow into the communication hole 24c can be further facilitated.

[Modification 3]
FIG. 7 shows a modification 3. In this modification 3, the shape of the communication hole 24c is different from that of the first embodiment.

That is, in this modification, each communication hole 24c is formed in a long hole shape that is long in the circumferential direction of the irradiation housing 24.

According to this configuration, the distance between the adjacent communication holes 24c can be narrowed as compared with the case where each communication hole 24c is formed by a simple circular hole. As a result, the external air flow h outside the irradiation housing 24 can be efficiently guided into each communication hole 24c in the entire circumferential direction.

[Embodiment 2]
FIG. 8 shows the second embodiment. In the second embodiment, the configuration of the irradiation housing 24 is different from that of the first embodiment and each modification.

That is, in the present embodiment, the irradiation housing 24 has a double tubular structure including a first housing 241 and a second housing 242 that surrounds the outside of the first housing 241. Then, the first housing 241 corresponds to the first outer cylinder portion, and the second housing 242 corresponds to the second outer cylinder portion. Both the first and second housings 241,242 are made of an inverted triangular pyramid-shaped tubular member, and the space 24a in the first housing 241 and the space 24e between the first and second housings 241,242 are shield gases, respectively. It constitutes a supply channel. The space 24a in the first housing 241 is also used as an optical path for the laser beam L that has passed through the condenser lens 23, as in the first embodiment.

A plurality of communication holes 24c are formed at the tip of the second housing 242. The shape and arrangement of the communication holes 24c are the same as those in the first embodiment. Each communication hole 24c is formed so as to communicate the space 24e as a shield gas supply path formed between the second housing 242 and the first housing 241 and the radial outer outer space of the second housing 242. Has been done.

According to this configuration, the external air flow h outside the second housing 242 is introduced from the communication hole 24c into the space 24e by the negative pressure of the shield gas flow g2 flowing in the space 24e outside before developing into the vortex. Is sucked into. Therefore, it is possible to avoid the problem of the spread of the shield gas flow g1 caused by the generation of the vortex flow described above. Therefore, the same effect as that of the first embodiment can be obtained. Further, the external air flow h sucked from the communication hole 24c does not enter the inner space 24a (the side close to the supply point of the powder material P). Therefore, it is possible to prevent the external air flow h from being mixed with the shield gas flow g2 flowing in the inner space 24a and reacting with the powder material P.

[Other embodiments]
Although one embodiment of the present invention has been described above, the specific embodiments that the present invention can take are not limited thereto.

In each of the embodiments and modifications, the irradiation housing 24 is arranged so as to surround the outside of the supply nozzle 11, and the space 24a between the outer peripheral surface of the supply nozzle 11 and the inner wall surface of the irradiation housing 24 is the laser beam L. Although the configuration used as the optical path and the shield gas supply path has been described, the present invention is not limited to this, and for example, as shown in FIG. 9, the shield gas supply path and the optical path may be provided separately. .. In this example, a supply nozzle 12 having an annular powder supply path 12a is used, and an outer cylinder housing 26 (an example of an outer cylinder portion) is arranged so as to surround the outside of the supply nozzle 12 (an example of a supply path forming member). ing. The space 26a inside the supply nozzle 12 is used as an optical path for the laser beam L, and the space 26b between the outer peripheral surface of the supply nozzle 12 and the outer cylinder housing 26 is used as a shield gas supply path. A communication hole 26c is formed at the lower end of the outer cylinder housing 26 as in each embodiment. As a result, the external air flow h induced on the outside of the outer cylinder housing 26 can be sucked into the outer space 26b as the shield gas flow path from the communication hole 26c before developing into a vortex flow. Therefore, it is possible to obtain the same effect as that of each of the above-described embodiments. The supply nozzle 12 is not limited to the configuration having the annular powder supply path 12a, and may be, for example, a multi-nozzle having a plurality of discharge ports arranged in the circumferential direction.

Further, in each of the above-described embodiments, the moving mechanism unit 3 is configured to be able to change the relative position between the work W and the machining head 2 by moving the machining head 2, but the present invention is not limited to this. That is, the moving mechanism unit 3 is configured to change both the machining head 2 and the work W, or move the work W with respect to the fixed machining head 2 to change the relative positions of the two. May be. Further, the change of the relative position between the work W and the processing head 2 is not limited to the three-dimensional space, and may be performed in the two-dimensional plane.

The present invention also includes any combination of the above embodiments and modifications.

Again, the description of the embodiments described above is exemplary in all respects and not restrictive. Modifications and changes can be made as appropriate for those skilled in the art. The scope of the invention is indicated by the claims, not by the embodiments described above. Further, the scope of the present invention includes modifications from the embodiments within the scope of the claims and within the scope of the claims.

P Powder material L Laser light S Planned laminating surface 1 Laser laminating modeling device 10 Powder material supply unit 11 Supply nozzle (supply path forming member)
11a Powder material supply path 12 Supply nozzle (supply path forming member)
12a Powder material supply path 20 Laser irradiation part 24 Irradiation housing (outer cylinder part)
24a space (optical path, shield gas supply path)
24c Communication hole 24e Space (shielded gas supply path)
26 Outer cylinder housing (outer cylinder part)
26a Space (optical path)
26b Space (shielded gas supply path)
26c Communication hole 30 Shielded gas supply unit 241 1st housing (1st outer cylinder part)
242 Second housing (second outer cylinder)

Claims (7)

A powder material supply unit that includes a supply channel forming member that forms a supply path for the powder material and supplies the powder material toward the planned stacking surface via the supply path, and a powder material supply unit that supplies the powder material to the planned stacking surface. A laser irradiation unit that melts and solidifies the powder material to form a cured layer by irradiating the powder material with a laser beam, and an outer peripheral surface that surrounds the outer peripheral surface of the supply path forming member. An outer cylinder portion that forms a shield gas supply path between the two, and a shield gas supply section that supplies the shield gas so as to surround the outside of the region where the powder material is supplied on the planned stacking surface through the shield gas supply path. It is a laser laminated molding device equipped with
The tip portion of the outer cylinder portion, which is the end portion on the discharge side of the shield gas, communicates the shield gas supply path inside the outer cylinder portion in the radial direction and the external space outside the radial direction of the outer cylinder portion. A laser laminated molding apparatus characterized in that a communication hole is formed. The outer cylinder portion has a double cylinder structure including a first outer cylinder portion and a second outer cylinder portion that surrounds the outside of the first outer cylinder portion.
The space between the supply path forming member and the first outer cylinder portion and the space between the first outer cylinder portion and the second outer cylinder portion each form the shield gas supply path.
The communication hole is formed in the tip end portion of the second outer cylinder portion, and is formed between the second outer cylinder portion and the first outer cylinder portion, and the shield gas supply path, and the second outer cylinder portion. The laser laminated molding apparatus according to claim 1, wherein the laser laminated molding apparatus is formed so as to communicate with an outer external space. A plurality of the communication holes are provided, and the communication holes are provided.
The laser stacking according to claim 1 or 2, wherein the plurality of communication holes are arranged over the entire circumference at intervals from each other in the circumferential direction of the outer cylinder portion in which the communication holes are formed. Modeling equipment. The laser laminated molding apparatus according to claim 3, wherein the plurality of communication holes are formed in a long hole shape that is long in the axial direction of the outer cylinder portion in which the communication holes are formed. The laser laminated molding apparatus according to claim 3, wherein the plurality of communication holes are formed in a long hole shape that is long in the circumferential direction of the outer cylinder portion in which the communication holes are formed. The one according to any one of claims 1 to 5, wherein the communication hole is inclined toward the tip portion side from the radial outer side to the inner side of the outer cylinder portion in which the communication hole is formed. Laser laminated modeling equipment. The one according to any one of claims 1 to 6, wherein the shield gas supply path is also used as an optical path for laser light emitted from the laser irradiation unit toward the planned stacking surface. Laser laminated modeling equipment.

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