In a three-dimensional shaping device, a region of an elevatable/lowerable table 2 for forming a powder layer and a region of a powder supply device are divided by a shield plate, an inert gas injection port is provided in the former region, the shield plate can be freely opened or closed so that a powder spraying squeegee traveling on the table is passed through, or a pipe which supplies powder from the powder supply device to the powder spraying squeegee which has traveled to the side of the shield plate penetrates through the shield plate, or a part of the shield plate is the powder supply port for the powder spraying squeegee which has traveled to the side of the shield plate and the pipe protrudes at a lower part and a sintering device applies a laser beam via a transparent region in a ceiling of a chamber.

BACKGROUND OF THE INVENTION

Technical Field

The present invention relates to a three-dimensional shaping device which realizes the multilayering of powder layers, the sintering of the powder layers with a laser beam and furthermore the cutting of the individual layers after the completion of the sintering.

Background Art

In the case of the three-dimensional shaping device described above, in a region on a table within a chamber, the multilayering and sintering of a plurality of powder layers are performed, thereafter the cutting is performed, and the step of performing the multilayering and sintering of the powder layers and the cutting afterward as described above is repeated.

In the case of three-dimensional shaping, in order to prevent metal powder from being oxidized at the stage of sintering, a chamber is filled with an inert gas such as nitrogen or argon.

However, in a conventional technique, an inert gas is supplied not only to a region of a table and the vicinity thereof where shaping of a three-dimensional article is performed, but also to a region where a powder supply device is present.

For example, in Patent Document 1, a cartridge portion in which an inert gas is stored is installed in the neighborhood of a material storage frame 24 (FIG. 1 and paragraphs [0050] and [0051]), and in the case of such an arrangement, the inert gas supplied from an enclosure 50 is inevitably made to flow also to the side of the powder supply device.

In Patent Document 2, it is proposed that an injection port and a suction port for an inert gas are provided, then the inert gas is made to flow locally to a region to which an optical beam is applied and thus the inert gas is economically utilized.

However, in a case where an inert gas, is made to flow locally, before sintered powder is cooled, the contact of the sintered powder with the inert gas is completed, and the sintered powder is brought into contact with air, with the result that it is impossible to realize sufficient prevention of oxidization.

In Patent Document 3, a shroud 7 in a state where the shroud 7 covers a powder layer 13, a sintering device, that is, an optical beam application means 5, a powder supply device, that is, a powder supply means 3, and a powder spraying machine, that is, a powder smoothing means 4 are integrally provided in three-dimensional directions, and thus moved on a shaping bed 2, with the result that the amount of inert gas used is reduced (abstract, selected diagram in FIG. 1 and paragraph [0024]).

However, the integral configuration of the movement in the three-dimensional directions described above is inconvenient to operate as a device, and the control thereof is extremely complicated in that it is impossible to perform a simple operation in which a table is made elevatable/lowerable and in which then a powder spraying squeegee is independently moved.

As described above, in the conventional technique, with the relatively simple configuration, the efficient use of the inert gas is proposed.

PRIOR ART DOCUMENTS

Patent Documents

Patent Document 1: Japanese Published Unexamined Patent Application No. 2010-037599

Patent Document 2: Re-publication of PCT International Publication No. 2011-049143

Patent Document 3: Japanese Published Unexamined Patent Application No. 2014-125643

SUMMARY OF INVENTION

Technical Problem

An object of the present invention is to provide a configuration of a three-dimensional shaping device in which, in the processing of a three-dimensional shaped article, an elevatable/lowerable table and a powder spraying squeegee traveling on the table are adopted and in which thus it is made possible to efficiently use an inert gas.

Solution to Problem

In order to achieve the above object, the basic configurations of the present invention are as follows:(1) A three-dimensional shaping device, comprising:

at least one chamber,

a region of an elevatable/lowerable table for forming a powder layer within the at least one chamber and a vicinity thereof,

a region of a powder supply device within the at least one chamber and a vicinity thereof

an inert gas injection port provided in the region of the elevatable/lowerable table,

a shield plate to prevent leakage of the inert gas from the region of the elevatable/lowerable table, the shield plate dividing the region of the elevatable/lowerable table from the region of the powder supply device,

a powder spraying squeegee moving on the powder layer,

the shield plate is constructed to be freely opened or closed so that the powder spraying squeegee traveling across the table is adapted to pass through the shield plate,

a sintering device which applies a laser beam to a shaping region of a three-dimensional shaped article on the table via a transparent region in a ceiling of the at least one chamber,

a horizontal-direction drive mechanism for the powder spraying squeegee, and

another shield plate divides:a) a region of the horizontal-direction drive mechanism for the powder spraying squeegee and a vicinity thereof andb) the region of the table and the vicinity thereof.(2) A three-dimensional shaping device, comprising:

at least one chamber,

a region of an elevatable/lowerable table for forming a powder layer within the at least one chamber and a vicinity thereof,

a region of a powder supply device within the at least one chamber and a vicinity thereof,

an inert gas injection port provided in the region of the elevatable/lowerable table,

a shield plate to prevent leakage of the inert gas from the region of the elevatable/lowerable table, the shield plate dividing the region of the elevatable/lowerable table from the region of the powder supply device,

a powder spraying squeegee moving on the powder layer,

a pipe which supplies powder dropped from the powder supply device to the powder spraying squeegee which has traveled to a side of the shield plate penetrates through the shield plate,

a sintering device which applies a laser beam to a shaping region of a three-dimensional shaped article on the table via a transparent region in a ceiling of the at least one chamber,

a horizontal-direction drive mechanism for the powder spraying squeegee, and

another shield plate divides:a) a region of the horizontal-direction drive mechanism for the powder spraying squeegee and a vicinity thereof andb) the region of the table and the vicinity thereof.(3) A three-dimensional shaping device, comprising:

at least one chamber,

a region of an elevatable/lowerable table for forming a powder layer within the at least one chamber and a vicinity thereof,

a region of a powder supply device within the at least one chamber and a vicinity thereof,

an inert gas injection port provided in the region of the elevatable/lowerable table,

a shield plate to prevent leakage of the inert gas from the region of the elevatable/lowerable table, the shield plate dividing the region of the elevatable/lowerable table from the region of the powder supply device,

a powder spraying squeegee moving on the powder layer,

a part of a region of the shield plate forms a powder supply port for the powder spraying squeegee which has traveled to a side of the shield plate,

a pipe through which powder passes through when dropping from the supply port is provided to protrude at a lower part of the shield plate,

a sintering device which applies a laser beam to a shaping region of a three-dimensional shaped article on the table via a transparent region in a ceiling of the at least one chamber,

a horizontal-direction drive mechanism for the powder spraying squeegee, and

another shield plate divides:a) a region of the horizontal-direction drive mechanism for the powder spraying squeegee and a vicinity thereof andb) the region of the table and the vicinity thereof.(4) The three-dimensional shaping device of any one of the above (1) to (3), which is characterized in that a region of a horizontal-direction drive mechanism for the powder spraying squeegee and a vicinity thereof and the region of the table and the vicinity thereof are divided by the shield plate.

Advantageous Effects of Invention

In the three-dimensional shaping devices of the basic configurations (1), (2) and (3), the region of the powder supply device and the vicinity thereof are basically not filled with the inert gas, and it is made possible to prevent the three-dimensional shaped article from being oxidized at the stage of sintering and the subsequent stages.

Moreover, in the case of the basic configuration (4) described above, the region of the horizontal-direction drive mechanism for the powder spraying squeegee and the vicinity thereof are not filled with the inert gas, and it is possible to prevent the oxidization described above.

DESCRIPTION OF EMBODIMENTS

In any of the basic configurations (1), (2) and (3), the region of the table2and the vicinity thereof and the region of the powder supply device30and the vicinity thereof are divided by the shield plate6, the inert gas injection port is provided in the former region and the sintering device4is provided which applies a laser beam to the shaping region of the three-dimensional shaped article10via the transparent region81in the ceiling8of the chamber1.

The ceiling8is preferably in a hermetically sealed state between a wall surrounding the region of the table2and the vicinity thereof and the shield plate6dividing both regions.

In the case of the basic configuration (1), as shown inFIG. 3(a), in order for the powder spraying squeegee31to receive the supply of the powder from the powder supply device30, it is essential to bring the shield plate6into an open state, and thus a small amount of inert gas cannot be prevented from leaking, via the opening portion60of the shield plate6, to the side of the region of the powder supply device30and the vicinity thereof.

However, as shown inFIG. 3(b), at the stages of the forming and the sintering of the powder layer, the shield plate6is brought into a closed state and the amount of inert gas jetted to the region of the table2and the vicinity thereof is adjusted, thus it is sufficiently possible to make up for the leaked inert gas described above and to fill the regions.

Moreover, in the powder spraying squeegee31, the supply of the powder to the powder spraying squeegee31is not performed for every layer in the multilayers, but the storage volume for the powder which makes it possible to perform the supply for every multilayer, specifically, every four or more layers is set, and thus it is possible to lower the degree of the leakage described above.

In the case of the basic configuration (2), as shown inFIGS. 4(a) and 4(b), the pipe33which supplies the powder dropped from the powder supply device30to the powder spraying squeegee31which has reached to the side of the shield plate6penetrates through the shield plate6.

In the case of the basic configuration (3), as shown inFIGS. 5(a) and 5(b), a part of the region of the shield plate6is used as the powder supply port for the powder spraying squeegee31which has reached to the side of the shield plate6, and the pipe33through which the powder passes when dropping downward from the supply port is provided to protrude at a lower part.

In the case of the basic configurations (2) and (3), it is possible to prevent the inert gas from reaching to the region of the powder supply device30and the vicinity thereof and the basic configurations (2) and (3) are superior to the basic configuration (1) in that the inert gas is efficiently utilized.

In the case of the basic configuration (2), it is also possible to obtain an effect of lowering the degree of the oxidization of the powder in storage by the inert gas entering into the side of the powder supply device30through opening outlet of the powder.

However, even in the basic configurations (1) and (3), in particular, by filling the powder supply device30with the inert gas, it is naturally possible to obtain the same effect.

It is to be noted that, in the case of the sintering device4using a laser beam, it is possible to realize the sintering via the transparent region81of the ceiling8, whereas in the case of an electron beam, since it is impossible to transmit the transparent region81, thus an electron beam is not adopted in the basic configurations (1), (2) and (3).

Although in the three-dimensional shaping device, the horizontal-direction drive mechanism32for alternately moving the powder spraying squeegee31to the side of the powder supply device30and to the side opposite thereto is provided, in the basic configurations (1), (2) and (3), it is not essential to divide, with the shield plate6, the region of the horizontal-direction drive mechanism32and the vicinity thereof and the region of the table2and the vicinity thereof, andFIGS. 4 and 5show such a case.

By contrast, based on the configurations of the basic configurations (1), (2) and (3), the basic configuration (4) is characterized in that the region of the horizontal-direction drive mechanism32for the powder spraying squeegee31and the vicinity thereof and the region of the table2and the vicinity thereof are divided by the shield plate6, andFIGS. 3(a) and 3(b)show the basic configuration (4) in a case based on the basic configuration (1) (illustration of the basic configuration (4) based on the basic configurations (2) and (3) is omitted).

With the characteristics described above, it is possible to prevent the former region from being filled with the inert gas.

It is to be noted that the horizontal-direction drive mechanism32for the powder spraying squeegee31naturally has a drive source, and the same is true for the horizontal-direction drive mechanism42for the sintering device4and the three-dimensional-direction drive mechanism52for the main shaft5which will be described later.

FIGS. 6(a) and 6(b)show embodiments which are characterized in that, a ball screw or a chain for movement92which moves the powder spraying squeegee31in the horizontal direction is provided in the region of the table2and the vicinity thereof, and in which a rotation shaft71that transmits rotation drive to the ball screw or the chain for movement92penetrates through the shield plate6and is coupled to the horizontal-direction drive mechanism32, andFIG. 6(a)shows the embodiment in which the rotation shaft71is engaged with the ball screw92andFIG. 6(b)shows the embodiment in which the rotation shaft71is engaged with the chain for movement92(inFIGS. 6(a) and 6(b), the illustration of a specific configuration in which the powder is supplied from the powder supply device30to the powder spraying squeegee31is omitted).

In the case of the embodiment described above, since almost no gap is formed between the rotation shaft71and the shield plate6, it is unlikely that the inert gas leaks from the region of the table2and the vicinity thereof to the region of the horizontal-direction drive mechanism32for the powder spraying squeegee31and the vicinity thereof.

FIG. 7shows an embodiment which is characterized in that, a support member34that supports the powder spraying squeegee31and that is moved in the horizontal direction together with the powder spraying squeegee31is fixed to a door72that slides within the shield plate6, and in which the door72has a horizontal width larger than that of the shield plate6such that a state where an opening portion is not formed in the sliding is made possible to be realized and then the door72is coupled to the horizontal-direction drive mechanism32(it is to be noted that, also inFIG. 7, the illustration of a specific configuration in which the powder is supplied from the powder supply device30to the powder spraying squeegee31is omitted).

In the embodiment described above, since the length of the door72is designed such that even when the door72slides on the shield plate6, the opening portion is prevented from being formed between the door72and the shield plate6, the inert gas which fills the region of the table2and the vicinity thereof is prevented from leaking via the opening portion to the region of the horizontal-direction drive mechanism32for the powder spraying squeegee31and the vicinity thereof.

Both the state where the rotation shaft71penetrates through the shield plate6in the embodiment ofFIG. 6and the state where the door72slides on the shield plate6inFIG. 7are preferably in a hermetically sealed state.

For that, it is possible to realize the purpose by setting the shape of a gap formed between the rotation shaft71or the door72and the shield plate6and the distance necessary for passing through the gap such that, in the case where the inert gas and air flow through the gap, the flow resistance is extremely large to the extent that the passing-through amount can be disregarded.

In the basic configuration (4), it is possible to adopt any one of the embodiments which is characterized in that, as shown inFIG. 8-1, the main shaft5for cutting the sintered three-dimensional shaped article10and the three-dimensional-direction drive mechanism52for the main shaft5are provided within the region of the table2and the vicinity thereof, and the embodiment which is characterized in that, as shown inFIG. 8-2, the shield plate6for dividing the region of the table2and the vicinity thereof and the region of the horizontal-direction drive mechanism32for the powder spraying squeegee31and the vicinity thereof is made so as to be freely opened or closed and in which the three-dimensional-direction drive mechanism52for the main shaft5for cutting the sintered three-dimensional shaped article10is provided on the side of the region of the horizontal-direction drive mechanism32for the powder spraying squeegee31and the vicinity thereof (it is to be noted that, also inFIGS. 8-1 and 8-2, the illustration of a specific configuration in which the powder is supplied from the powder supply device30to the powder spraying squeegee31is omitted).

In each of the embodiments described above as well, basically, it is possible to reduce the filling of the region of the horizontal-direction drive mechanism32for the powder spraying squeegee31and the vicinity thereof with the inert gas.

However, it is impossible to deny the fact that the embodiment in which, as in the embodiment ofFIG. 8-2, the shield plate6of the basic configuration (4) is made so as to be freely opened or closed and then in which the shield plate6is opened at each time the main shaft5is moved, is inferior to the embodiment in which, as inFIG. 8-1, the three-dimensional-direction drive mechanism52for the main shaft5is provided within the region of the table2and the vicinity thereof in the point that a small amount of inert gas leaks from the region of the table2and the vicinity thereof via the opening portion60at the stage of opening.

However, at the stage of the forming and the sintering of the powder layer, the amount of inert gas jetted to the region of the table2and the vicinity thereof is adjusted, and thus it is sufficiently possible to make up for and load the leaked inert gas as described above.

Moreover, in the case where, in the embodiment ofFIG. 8-2, a method is adopted where, one table2, one powder supply device30and one powder spraying squeegee31, and one sintering device4are adopted for one chamber1, and then the cutting with the main shaft5is performed after the completion of all steps of the multilayering of the powder with the powder spraying squeegee31and the sintering of the powder with the sintering device4, since, at the stage of the cutting, there is already a very low possibility that metal powder involving sintering is oxidized, hence it is possible to sufficiently avoid the damage of the leakage.

A description will be given below according to Examples.

Example 1 is characterized in that, as shown inFIGS. 1-1(a) and1-1(b), the table2is provided in each of the regions on the side where two chambers1are adjacent to each other, the powder supply device30is provided in each of the regions where the two chambers1are not adjacent to each other, one main shaft5is provided which is moved by the three-dimensional-direction drive mechanism52provided within the regions where the two chambers1are adjacent to each other, one sintering device4is provided which is moved by the horizontal-direction drive mechanism42provided on the upper side of the ceiling8of the regions where the two chambers are adjacent to each other and a control device is provided which alternately moves the one main shaft5and the one sintering device4between the two chambers1(FIGS. 1-1(a) and1-1(b) showcases which are based on the basic configuration (1)).

Due to the characteristics described above, Example 1 is significant as compared with the case of the conventional technique, in terms of economical cost, in the point that it suffices to provide one powder multilayer device and one main shaft5for two chambers1.

Moreover, by making it possible to simultaneously perform the multilayering step and the sintering step of the powder layer and the cutting step in the two chambers1, it becomes possible to avoid the occurrence of a waiting time of the main shaft5for all the time of the multilayering step and the sintering step and the occurrence of a waiting time of the sintering device4for all the time of the cutting step.

It is to be noted that, in Example 1, since the sintering device4and the main shaft5need the control device capable of alternately moving the sintering device4and the main shaft5between the two chambers1, it is essential that the three-dimensional-direction drive mechanism52for the main shaft5is inevitably provided within the region of the table2and the vicinity thereof, that is, the three-dimensional-direction drive mechanism52for the main shaft5is based on the embodiment ofFIG. 8-1.

In Example 1, in order to realize the multilayering, the sintering, the cutting and the alternate movement, as shown in the flow chart ofFIG. 1-3, the control method can be adopted in which the computer for controlling the multilayering and the sintering controls the movement of the sintering device4and in which the computer for controlling the cutting controls the movement of the main shaft5.

Furthermore, as shown inFIG. 1-3, the control method can also be adopted in which, in addition to the computer for controlling the multilayering and the sintering and the computer for controlling the cutting, the computer for controlling the movement of the sintering device4and the main shaft5is provided and is operated with the computer for controlling the multilayering and the sintering and the computer for controlling the cutting in a coordinated manner.

Example 2 is characterized in that as shown inFIGS. 2-1(a) and2-1(b), the table2is provided in each of the regions on the side where two chambers1are adjacent to each other, one powder supply device30is provided on one side of the regions where the two chambers1are not adjacent to each other, one main shaft5is provided which is moved by the three-dimensional-direction drive mechanism52provided within the regions where the two chambers1are adjacent to each other, one sintering device4is provided which is moved by the horizontal-direction drive mechanism42provided on the upper side of the ceiling8of the regions where the two chambers1are adjacent to each other and a control device is provided which alternately moves the one main shaft5, and the one sintering device4and one powder spraying squeegee31corresponding to the one powder supply device30between the two chambers1(it is to be noted thatFIGS. 2-1(a) and2-1(b) show cases which are based on the basic configuration (2), andFIG. 2-1(a) shows a state where the powder spraying squeegee31indicated by dotted lines receives the supply of the powder via the pipe33from the powder supply device30).

In Example 2 as well, the same actions and effects as in Example 1 can be achieved, and it is essential that the main shaft5for performing the cutting is provided in the region of the table2and the vicinity thereof.

In Example 2 as well, in order to realize the alternate movement, as shown in the flow chart ofFIG. 2-2, the control method can be adopted in which the computer for controlling the multilayering and the sintering controls the movement of the powder spraying squeegee31and the sintering device4and in which the computer for controlling the cutting controls the movement of the main shaft5.

Furthermore, as shown in the flow chart ofFIG. 2-3, the control method can also be adopted in which, in addition to the computer for controlling the multilayering and the sintering and the computer for controlling the cutting, the computer for controlling the movement of the powder spraying squeegee31and the sintering device4, and the main shaft5is provided and is operated with the computer for controlling the multilayering and the sintering and the computer for controlling the cutting in a coordinated manner.

INDUSTRIAL APPLICABILITY

A plurality of embodiments and Examples have been described as above, and the present invention in which, at the stage of the sintering and the subsequent stages up to cooling, the inert gas for preventing the oxidization of the metal powder is efficiently used can be utilized in all fields of three-dimensional shaping devices.

REFERENCE SIGNS LIST

1: Chamber10: Shaped article2: Table30: Powder supply device31: Powder spraying squeegee32: Horizontal-direction drive mechanism for powder spraying squeegee33: Pipe34: Support member for powder spraying squeegee4: Sintering device41: Holding member for sintering device42: Horizontal-direction drive mechanism for sintering device5: Main shaft51: Holding member for main shaft52: Three-dimensional-direction drive mechanism for main shaft6: Shield plate60: Opening portion formed in shield plate71: Rotation shaft72: Door8: Ceiling81: Transparent region92: Ball screw or chain for movement for moving powder spraying squeegee in horizontal direction93: Coupling rotation portion of rotation shaft and ball screw or chain for movement