JP6908438B2 - Printing equipment - Google Patents

Description

The present invention relates to a processing method, a processing system, and a processing program for irradiating a work piece with a laser to process the work piece.

A laser processing method for forming a modeled object having a predetermined processed surface by irradiating the workpiece with a laser and a laser processing apparatus using the laser processing method are known.

For example, Patent Document 1 describes in an artificial tooth making apparatus that changes the relative positional relationship between a tool and a work in three dimensions based on machining data and cuts the work with the tool to make an artificial tooth. A creating means for creating marking data, which is data representing an area in which an artificial tooth produced at a predetermined position of the work is accommodated, and light is emitted to the surface of the work based on the marking data created by the creating means. It has a marking means for irradiating and marking the surface of the work, and the marking means is a laser for drawing a region based on the marking data, and marking is performed by emitting a laser beam to the work. An artificial tooth making apparatus, characterized in that it is performed, is disclosed.

Japanese Unexamined Patent Publication No. 2017-074259

The above-mentioned artificial tooth making apparatus performs processing by irradiating a work piece with a laser beam having a constant focusing diameter regardless of the complexity of the processed surface. According to the configuration of such an artificial tooth making apparatus, if the processed surface has a recess whose size is smaller than the condensing diameter of the laser light, it is not possible to irradiate the laser beam to form the recess. If the laser beam is irradiated to the concave portion, the surface other than the surface to be processed is processed, and a concave portion having a size larger than the desired concave portion is formed. That is, the more complicated the desired processed surface is, the more difficult it becomes to process with high accuracy.

Therefore, the present invention has been made in view of the above circumstances, and the problem to be solved by the present invention is a processing method and processing system capable of processing with high accuracy even if a desired processing surface becomes complicated. And to provide a machining program.

The main invention for achieving the above object is to set a processing diameter according to the uneven shape of the predetermined processing surface in the vicinity of the processing point on the predetermined processing surface in order to form a modeled object having a predetermined processing surface. This is a processing method including a step of irradiating the laser with the laser toward the processing point. Other features of the present invention will be clarified by the description of the description and drawings described later.

According to the present invention, it is possible to provide a processing method, a processing system and a processing program capable of processing with high accuracy even if a desired processing surface becomes complicated.

It is a figure explaining the structure of the processing system which concerns on one Embodiment of this invention. It is a figure explaining the definition of the processing diameter of a laser. It is a figure explaining the processing diameter acquisition process which concerns on one Embodiment of this invention. It is sectional drawing which explains the laser irradiation process which concerns on one Embodiment of this invention. It is sectional drawing which explains the laser irradiation process which concerns on one Embodiment of this invention. It is sectional drawing which explains the laser irradiation process which concerns on one Embodiment of this invention.

=== Embodiment ===
Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the embodiments described below are provided with various technically preferable limitations for carrying out the present invention. Therefore, the scope of the present invention is not limited to the following embodiments and illustrated examples.

[Processing system configuration]
First, the configuration of the processing system 100 according to the present embodiment will be described in detail. FIG. 1 is a diagram illustrating a configuration of a processing system 100 according to the present embodiment. The processing system 100 according to the present embodiment includes a data creation device 200, a control device 300, and a processing device 400.

The data creation device 200 is an apparatus for creating data (processing data) of a predetermined processing surface formed on the workpiece 500. The data creation device 200 outputs the created processing data to the control device 300.

The data on the processed surface is data used by the control device 300 when processing the target modeled object. The processing data is created by the data creation device 200 based on the three-dimensional data of the target modeled object and the three-dimensional data of the workpiece 500. For example, when processing a prosthesis for dentistry, processing data is created using three-dimensional data obtained by scanning the oral cavity with a CCD camera or X-ray CT. The three-dimensional data of the target object is STL data, solid data used in three-dimensional CAD, or data such as 3MF or AMF used in a 3D printer. The format of the output data is not particularly limited as long as it can be used by the control device 300.

The processing apparatus 400 is an apparatus for irradiating the workpiece 500 with a laser to form a modeled object having a predetermined processed surface. As the workpiece 500, a material that transmits a laser (transparent material) or a material that does not transmit a laser (opaque material) can be used. The transparent material is, for example, a glass material or a resin material having high light transmittance (for example, an acrylic resin). The opaque material is, for example, a zirconia material used as a denture material or a general metal material. The light transmittance of the transparent material does not have to be 100%, and may be a value that allows the laser to reach the processing region inside the material and process it.

The configuration of the processing apparatus 400 according to the present embodiment will be described. The processing device 400 according to the present embodiment includes an irradiation unit 402, a holding unit 404, and a drive mechanism 406.

The irradiation unit 402 irradiates the workpiece 500 with a laser. In the present embodiment, the irradiation unit 402 includes an oscillator of the laser, a lens group for guiding the laser from the oscillator to the workpiece 500, a galvanometer mirror, and an optical device such as an attenuator for adjusting the laser intensity. The type of laser is not particularly limited as long as it can process the workpiece 500. For example, when processing a metal material, a general infrared laser for thermal processing can be used. Alternatively, when directly processing the inside of the material, an ultrashort pulse laser can be used. An ultrashort pulse laser is a laser having a pulse width of several picoseconds to several femtoseconds. Ablation processing (non-thermal processing) can be performed by irradiating a predetermined position inside the workpiece 500 with an ultrashort pulse laser for a short time. In the ablation processing, the portion melted by the laser is instantly evaporated, scattered and removed, so that the processed portion is less damaged by heat as compared with the general laser processing (thermal processing). The ablation process is particularly effective for processing small objects such as prostheses used in dentistry.

The holding portion 404 holds the workpiece 500. The method for holding the workpiece 500 is not particularly limited as long as the held workpiece 500 can be moved and rotated along the five axes. For example, as in the case of cutting with a conventional 5-axis machining apparatus, a method of holding a disk-shaped workpiece 500 by sandwiching it with a clamp, or a method of adhering a metal pin to a block-shaped workpiece 500 is performed. A method of inserting the pin into the holding portion 404 and holding the pin is possible.

The drive mechanism 406 relatively moves the irradiation unit 402 and the holding unit 404. The drive mechanism 406 includes a drive motor and the like. The processing apparatus 400 according to the present embodiment has five drive axes (X-axis, Y-axis, Z-axis, A-rotation axis (rotation-axis around X-axis), B-rotation axis (rotation-axis around Y-axis)). Have.

The control device 300 is a device for controlling the processing device 400. Specifically, the control device 300 controls the drive mechanism 406 so that the laser can be irradiated to the position corresponding to the machining data inside the workpiece 500, and the irradiation unit 402 and the holding portion 404 (workpiece 500). Adjust the relative positional relationship with. Further, the control device 300 controls the irradiation unit 402 to adjust the focal position of the laser, the processing diameter of the laser to be irradiated, and the like, and irradiates the workpiece 500 with the laser for a predetermined time. do.

Here, the definition of "machining diameter" in the present specification will be described with reference to the drawings. FIG. 2 is a schematic view illustrating the processing diameter of the laser. In this example, the intensity distribution of the laser in a plane perpendicular to the optical axis of the laser is shown. Further, in this example, the intensity distribution of the laser is axisymmetric with respect to the optical axis of the laser, and has a substantially Gaussian distribution.

In order to process the workpiece 500, a laser intensity of a certain value or more corresponding to the material of the workpiece 500 is required. Assuming that the minimum laser intensity required for that purpose is I ₀ , the diameter of the region having the laser intensity I ₀ or more in the laser bundle is defined as the processing diameter φ in the present specification (FIG. 2 (a)).

In this embodiment, in particular, the control device 300 controls the irradiation unit 402 to irradiate the laser toward the processing point according to the uneven shape of the predetermined processing surface in the vicinity of the processing point on the predetermined processing surface. It is possible to adjust the processing diameter. The processing diameter φ of the laser can be adjusted or controlled by a plurality of methods, such as narrowing the beam on the optical axis with an aperture or the like. In particular, when processing with an ultrashort pulse laser, a photosphere in which a beam focused in the air turns molecules in the atmosphere into plasma is observed, and changes in the brightness and diameter of the photosphere can be confirmed according to the laser intensity. As an example, the workpiece 500 can be processed by the plasma-generated photosphere. In this case, the above-mentioned laser intensity I ₀ is the laser intensity required for plasma-forming molecules in the atmosphere, and the above-mentioned processing diameter φ corresponds to the diameter of the plasma-generated photosphere.

As another example, the processing diameter φ can be adjusted by adjusting the intensity I of the irradiating laser. That is, the intensity I of the irradiating laser can be adjusted to increase or decrease the peak while maintaining the width of the Gaussian distribution, and the processing diameter can be increased or decreased accordingly. The intensity I of the laser to be irradiated can be controlled by a method of directly controlling the output signal from the laser oscillator or by using an external optical system to control the intensity of the output laser light. As a method of controlling the laser intensity by an external optical system, for example, it can be adjusted by using an attenuator. As described above, the control device 300 according to the present embodiment has an attenuator for adjusting the intensity I of the laser. That is, the control device 300 according to the present embodiment can control the attenuator to adjust the machining diameter. FIG. 2B shows an example of switching to a laser having a processing diameter φ ′ smaller than the processing diameter φ by attenuating the laser intensity using an attenuator.

As another example, the machining diameter can be adjusted by adjusting the focusing diameter of the laser. _{The theoretical limit value of the minimum focusing diameter D 0} obtained when a single-mode laser is focused by a lens with a focal length f _{is approximately D 0} , where λ is the wavelength and D is the diameter of the incident laser. It is expressed as = 4λf / πD. That is, the focusing diameter can be adjusted by adjusting the focal length f of the lens, the wavelength λ of the laser, and the diameter D of the incident laser here, and it is possible to adjust the processing diameter. FIG. 2C shows an example of switching to a laser having a processing diameter φ ″ smaller than the processing diameter φ by reducing the focusing diameter.

Details will be given later in the description of the processing method, but in the present embodiment, adjusting the processing diameter of the laser uses the relationship between the laser irradiation condition and the processing diameter φ acquired in advance. The irradiation condition used in this embodiment is a laser intensity I.

[Processing method]
The processing method using the above-mentioned processing system 100 according to the present embodiment will be described in detail. The machining method using the machining system 100 described above according to the present embodiment is executed by the control device 300 controlling the machining device 400. The processing method according to the present embodiment includes a processing diameter acquisition step and a laser irradiation step.

The machining diameter acquisition step is a step of acquiring the relationship of the machining diameter with respect to the laser irradiation condition. The processing diameter acquisition process will be described in detail with reference to the drawings. FIG. 3 is a diagram illustrating a processing diameter acquisition process according to the present embodiment. Here, the laser irradiation condition is at least one laser irradiation condition selected from, for example, the above-mentioned laser intensity I, lens focal length f, laser wavelength λ, incident laser diameter D, and the like. As described above, in the present embodiment, the laser intensity I is used as the laser irradiation condition.

In the processing diameter acquisition process, a material 502 made of the same material as the workpiece 500 is prepared. Then, the material 502 is irradiated with the laser for each of the plurality of values of the parameter Δ related to the selected laser irradiation condition (in the present embodiment, the laser intensity I) (FIG. 3A). As a result, the diameter of the recess or through hole formed in the material 502 is regarded as the processing diameter φk (k = 1, 2, 3, ...), And a scatter diagram of the processing diameter measured with the parameter Δ is created. .. From this scatter plot, Δ is mathematically expressed as a function f (φ) of the machining diameter φ (FIG. 3 (b)). In this mathematical formula, the optimum mathematical formula is searched by assuming a functional form in advance. The function form at this time is not particularly limited, but for example, an nth-order function (n is an integer) may be assumed, and an nth-order function optimized by the least squares method may be searched.

The machining diameter acquisition step needs to be performed before the laser irradiation step. On the other hand, the machining diameter acquisition step does not have to be executed each time before forming the modeled object, and once this step is executed, this result can be reused in other laser irradiation steps to be executed later. can do.

The laser irradiation step is a step of irradiating a laser toward a processing point in order to form a modeled object having a predetermined processing surface S. The laser irradiation process will be described in detail with reference to the drawings. 4 to 6 are schematic cross-sectional views for explaining the laser irradiation process.

In the present embodiment, since STL data is assumed as the processing data, the shape of the processing surface S is represented by a set of triangles. Along with this, in the schematic cross-sectional views shown in FIGS. 4 to 6, the shape of the processed surface S is represented by a set of line segments. In these figures, any recesses on the processed surface S, including the line segment AC and the line segment BC, are shown. In this recess, it can be said that the closer to the point C, the finer the shape of the recess.

The laser used in the present embodiment is adjusted to have a machining diameter corresponding to the uneven shape of the predetermined machining surface S in the vicinity of the machining point on the predetermined machining surface S. The machining diameter is adjusted in the above-mentioned machining diameter acquisition step by using the relationship of the machining diameter with respect to the laser irradiation conditions acquired in advance. The laser irradiation condition used in this embodiment is the laser intensity. The laser intensity can be adjusted using an attenuator.

In this embodiment, a laser having a processing diameter selected from _{a plurality of types of processing diameters (φ 1} > φ ₂ >...> φ _n ) is used according to the uneven shape of the processed surface S. _{First, the first processing diameter φ 1} which is the largest processing diameter among these is determined. The first processing diameter φ ₁ is not particularly limited, and may be, for example, a processing diameter of a degree used in a conventional processing method. When the first processing diameter phi ₁ is determined, using the equation obtained in the processing diameter acquiring step described above, the laser irradiation condition corresponding to the first processing diameter phi ₁ is determined. Then, as shown in FIG. 4 (a), machining path P ₁ for irradiating a laser is determined. Here, machining path P ₁ is the set of points the distance from the work surface S is first processing diameter phi ₁ of the half.

Then, as shown in FIG. 4 (b), using a laser having a first processing diameter phi _1, for processing a workpiece 500. At this time, the upper machining path P ₁ such that the focal point position of the laser is moved, the drive mechanism 406 is controlled. Here, a circle of diameter phi ₁ around the _{P 10} on the machining path _{P 1} is in contact with the line segment AC and the line segment BC. At this stage, the inside of the processed surface S is not processed, but on the other hand, an unprocessed region remains in the vicinity of the point C.

Then, the processing diameter of a laser processing apparatus 400 is output, switching from the first processing diameter phi ₁ to the second processing diameter phi _2. Here, the second processing diameter φ ₂ may be smaller than the first processing diameter φ _1, but in the present embodiment, the second processing diameter φ ₂ is determined as follows as an example.

First, a position at a predetermined distance ε from _{the point P 10} on the line segment connecting the point P _{10 and the point C is defined as the point P 20} . _Then, the line segment AC and the line segment ₂ the diameter of a circle second turning diameter φ in contact with the BC around the _{P 20.} When the second processing diameter φ ₂ is determined, the laser irradiation condition corresponding to _{the second processing diameter φ 2} is determined by using the mathematical formula Δ = f (φ) obtained in the above-mentioned processing diameter acquisition step. Then, as shown in FIG. 5 (a), machining path P ₂ is irradiated with a laser is determined. Here, the processing path P ₂ is a set of points whose distance from the processing surface S _{is half of the second processing diameter φ 2.}

Then, as shown in FIG. 5 (b), using a laser having a second processing diameter phi _2, machining the workpiece 500. At this time, the drive mechanism 406 is controlled so that the upper machining path P ₂ is the focal position of the laser to move. At this time, since the may be processed only areas not machined by the processing using a laser having a first processing diameter phi ₁ of the foregoing, the need to move the laser focal point position of the entire region of the machining path P ₂ do not have. By this step, in the region near the point C, the region that could not be processed by the processing using the laser having _{the first processing diameter φ 1 can be processed.}

Then, the processing diameter of a laser machining apparatus 400 outputs, to switch from the second processing diameter phi ₂ to the third processing diameter phi _3. The third processing diameter φ ₃ is smaller than the second processing diameter φ ₂ , and in the present embodiment _{, the third processing diameter φ 3} is determined as follows in the same manner as the method for determining _{the second processing diameter φ 2.} ..

First, on the line segment connecting the point P ₂₀ and the point C, the position of the distance ε from _{the point P 20 is defined as the point P 30} . _Then, the line segment AC and circle diameter of the third processing diameter phi ₃ of which is in contact with the segment BC around the _{P 30.} When the third processing diameter φ ₃ is determined, the laser irradiation condition corresponding to _{the third processing diameter φ 3} is determined by using the mathematical formula Δ = f (φ) obtained in the above-mentioned processing diameter acquisition step. Then, as shown in FIG. 6 (a), machining route P ₃ for irradiating a laser is determined. Here, the processing path P ₃ is the set of points the distance from the work surface S is half the third processing diameter phi _3.

Then, as shown in FIG. 6 (b), using a laser having a third working diameter phi _3, machining a workpiece 500. At this time, the drive mechanism 406 is controlled so that the upper machining path P ₃ is the focal position of the laser to move. At this time, since the may be processed only areas not machined by the processing using a laser with a second processing diameter phi ₂ of the foregoing, the need to move the laser focal point position of the entire region of the processing path P ₃ do not have. By this step, in the region near the point C, the region that could not be processed by the processing using the laser having _{the second processing diameter φ 2 can be processed.}

Using the same method as above, the kth processing diameter φ _k (k = 4, 5, ...) Was determined and a laser having _{the kth processing diameter φ k was used until the processing of an arbitrary recess was completed.} Repeat the processing. It may be repeated until the machining diameter reaches the limit value in the machining apparatus 400, or may be completed at a predetermined number of times. Further, the predetermined distance ε is arbitrary, and the same value may be used as in the present embodiment or different values may be used in repeating the above-mentioned method.

[Processing program]
The program for controlling the processing device 400 according to the present embodiment is read and executed by the control device 300.

The machining program according to the present embodiment is a program for causing the control device 300 to execute the above-mentioned machining method. That is, in the machining program according to the present embodiment, the control device 300 stores the data of the machining surface S formed on the workpiece 500 created by the data creation device 200. Next, the control device 300 is made to set the processing path of the laser to irradiate the workpiece 500 in order to form the modeled object having the processed surface S. Further, the control device 300 is made to adjust the machining diameter of the laser to be irradiated toward the machining point according to the uneven shape in the vicinity of the machining point on the machining surface S.

Adjusting the processing diameter of the laser that irradiates toward the processing point is adjusted according to the uneven shape in the vicinity of the processing point on the processing surface S. Specifically, adjusting the processing diameter of the laser is performed by using the relationship of the processing diameter with respect to the laser irradiation condition acquired in advance.

The machining method according to the present embodiment, the machining system 100 for executing the machining method, and the machining program have been described above. In the processing method according to the present embodiment, in order to form a modeled object having a predetermined processing surface, a laser having a processing diameter corresponding to the uneven shape of the predetermined processing surface in the vicinity of the processing point on the predetermined processing surface is used. Includes the step of irradiating toward the processing point.

According to the conventional processing method, processing is performed using a laser having a constant processing diameter regardless of the uneven shape of the processed surface. Therefore, when the processed surface has a concave portion having a size smaller than the processed diameter, there is a restriction that the laser cannot be irradiated toward the concave portion. Therefore, according to the conventional processing method, if the processing surface becomes complicated, it becomes difficult to process with high accuracy.

According to the processing method according to the present embodiment, the above-mentioned restrictions are relaxed, so that a recess having a size that cannot be formed by the conventional processing method can be formed. Therefore, according to the processing method according to the present embodiment, even if the processing surface becomes complicated, it is possible to process with high accuracy.

Further, according to the processing method according to the present embodiment, the conventional processing method can be used for the processing surface that can be processed by the conventional processing method, and the processing cannot be processed by the conventional processing method. Since processing is performed only on the surface using a laser having a processing diameter smaller than that of the conventional one, the processing time is not significantly prolonged.

According to the processing method according to the present embodiment, the processing diameter is adjusted by using the relationship of the processing diameter with respect to the laser irradiation condition acquired in advance. Thereby, the laser irradiation conditions for adjusting to a desired processing diameter can be freely selected.

A processing system 100 for carrying out the processing method according to the present embodiment described above can be configured. By carrying out using such a processing system 100, the same effect as described above can be obtained.

Further, a machining program for carrying out the machining method according to the present embodiment of the superior technique can be configured. By executing such a machining program in the machining system 100, the same effect as described above can be obtained.

It is also possible to supply a program to a computer by using a non-transitory computer readable medium with an executable program comprising a processing program for carrying out the processing method of the above embodiment. .. Examples of non-temporary computer-readable media include magnetic recording media (for example, flexible disks, magnetic tapes, hard disk drives), CD-ROMs (Read Only Memory), and the like.

Although the embodiment for carrying out the present invention has been described above, the above-described embodiment is for facilitating the understanding of the present invention, and is not for limiting the interpretation of the present invention. Further, the present invention can be modified or improved without departing from the spirit thereof, and the present invention also includes an equivalent thereof. The changes from the above embodiments will be described below. The changes described below may be applied in combination as much as possible.

100 ... Machining system 200 ... Data creation device 300 ... Control device 400 ... Machining device 402 ... Irradiation unit 404 ... Holding unit 406 ... Drive mechanism 500 ... Work piece 502 ・ ・ ・ Material

Claims (3)

In order to form a modeled object having a predetermined processing surface, a laser having a processing diameter corresponding to the uneven shape of the predetermined processing surface in the vicinity of the processing point on the predetermined processing surface is irradiated toward the processing point. a processing method comprising the step of,
A processing method characterized in that the processing diameter is adjusted by using the relationship of the processing diameter with respect to a laser irradiation condition acquired in advance . A data creation device that creates data on a predetermined machined surface to be formed on the work piece,
A processing device that irradiates the workpiece with a laser to form a modeled object having the predetermined processed surface.
A control device that controls the processing device, and adjusts the processing diameter of the laser that irradiates toward the processing point according to the uneven shape of the predetermined processing surface in the vicinity of the processing point on the predetermined processing surface. and a control device for,
A processing system characterized in that adjusting the processing diameter of the laser uses the relationship of the processing diameter with respect to the laser irradiation conditions acquired in advance. Stores the data of the processed surface to be formed on the work piece,
In order to form a modeled object having the processed surface, a processing path of a laser to irradiate the workpiece is set.
It is a machining program for causing a control device to adjust the machining diameter of the laser to be irradiated toward the machining point according to the uneven shape in the vicinity of the machining point on the machining surface .
Adjusting the processing diameter of the laser is a processing program characterized in that the relationship of the processing diameter with respect to the laser irradiation condition acquired in advance is used .

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