KR102101973B1 - 3d printing device including safety device for laser irradiation - Google Patents

Abstract

The present invention is to determine whether the laser output signal and the detection signal coincide and to accurately and quickly detect the failure and control error of the laser system, while having a safety device for laser emission to reduce the complexity of the error detection means It relates to a printing device.
A 3D printing apparatus having a safety device for laser emission according to the present invention includes a molding unit for supplying a material material for forming a molded object; A beam supply unit for forming a molding layer by supplying a beam to the material material supplied to the molding unit; A control unit generating a control signal for controlling the supply of the beam; A detection means having a sensor for detecting whether the beam is emitted from the beam supply unit, and generating a light detection result using the detection result of the sensor; And a detection unit that compares the light detection result with the control signal to detect whether the beam is emitted according to the control signal.

Description

3D printing device equipped with a safety device for laser emission {3D PRINTING DEVICE INCLUDING SAFETY DEVICE FOR LASER IRRADIATION}

The present invention relates to a 3D printing apparatus having a safety device for laser emission, and it is possible to accurately and quickly detect a failure and a control error of a laser system by determining whether the laser output signal and the detection signal match, and It relates to a 3D printing device having a safety device for laser emission to reduce the complexity.

3D printer means a device that can form a three-dimensional shape to be formed, and because of these advantages, its use in various fields is greatly increased.

The printing technology of these 3D printers is largely divided into a cutting type for cutting a lump of raw materials and a additive type (AM: Additive Manufacturing) in which a layer of raw materials is stacked up. Among them, the laminated type is Binder Jetting (BJ), Directed Energy Deposition (DED), Material Extrusion (ME), Material Jetting (MJ), and Powder Bed Fusion (PBF) : Powder Bed Fusion), Sheet Lamination (SL), VP Photopolymerization (VP).

Among various printing methods such as DED, PBF, and VP, lasers are generally used to supply light or heat to raw materials. The laser has the advantage of being capable of forming a fine structure due to high precision of control. As a method of using such a laser, a method in which a raw material is temporarily melted with heat supplied by a laser and then re-cured, or a powder or liquid is cured by a photoreaction by supplying light of a specific wavelength to the raw material is used.

On the other hand, in the printing method using a laser, when a malfunction of the laser occurs, there is a problem in that printing is omitted or unnecessary parts are printed. Particularly, since lasers are mainly used for the generation of microstructures, there is a problem in that the structures being manufactured must be discarded when such defects occur.

Despite these problems, there is a problem in that it is difficult to improve the reliability of the product due to the absence of detection and control means that accurately and quickly detects failures and control errors of the laser system and does not significantly increase the complexity of the printing device.

Korean Registered Patent 10-1705696 (Registration Date February 06, 2017)

Accordingly, an object of the present invention is to determine whether the laser output signal and the detection signal match and to accurately and quickly detect a failure and a control error of the laser system, while providing a safety device for laser emission to reduce the complexity of the error detection means. It is to provide a 3D printing apparatus having a.

In order to achieve the above object, a 3D printing apparatus having a safety device for laser emission according to the present invention includes a molding unit for supplying a material material for forming a molded object; A beam supply unit for forming a molding layer by supplying a beam to the material material supplied to the molding unit; A control unit generating a control signal for controlling the supply of the beam; A detection means having a sensor for detecting whether the beam is emitted from the beam supply unit, and generating a light detection result using the detection result of the sensor; And a detection unit that compares the light detection result with the control signal and detects whether the beam has been emitted according to the control signal.

The detecting means is characterized in that it further performs a function of relaying the control signal and transmitting it to the beam supply unit to detect whether a control signal has been generated.

The control signal is characterized in that it is a voltage signal or a current signal composed of a plurality.

The sensing means is characterized in that it relays an on / off signal for controlling the emission of the beam among a plurality of signals.

A material material supply unit for receiving the material material and supplying a material material for forming the molding layer; A material material transfer unit for supplying the material material to the molding unit and forming a material material layer for forming the molding layer; It characterized in that it further comprises a; material material receiving portion for receiving the material material remaining after forming the molding layer.

The sensing means is configured to further include a control intensity amplifying device for adjusting the detection intensity, the detection intensity of which is the time required for the sensor to detect the beam and the time required for the sensor to detect the beam. It is characterized by.

The 3D printing apparatus having a safety device for laser emission according to the present invention determines whether the laser output signal and the detection signal match and accurately and quickly detects a failure and a control error of the laser system, while increasing the complexity of the error detection means. It is possible to lower.

Through this, the 3D printing apparatus equipped with the safety device for laser emission according to the present invention can greatly improve the reliability of the apparatus while minimizing the increase in cost required to manufacture the apparatus.

1 is an exemplary view showing the structure of a 3D printing apparatus having a safety device for laser emission according to the present invention.
Figure 2 is an exemplary configuration showing a configuration for error detection of a 3D printing apparatus according to the present invention.
Figure 3 is an exemplary configuration showing a configuration for error detection of a 3D printing apparatus according to a second embodiment of the present invention.
Figure 4 is a configuration example showing the configuration of a conventional 3D printing apparatus.
5 is an exemplary view showing an example for explaining an abnormality determination process of the detection unit in the form of a table.

Hereinafter, with reference to the accompanying drawings, an embodiment of the present invention will be described so that those skilled in the art can easily implement. It should be noted that, in the accompanying drawings, the same reference number is used when the same number is indicated in the other drawings. In addition, in the description of the present invention, when it is determined that a detailed description of a related known function or known configuration may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted. In addition, some features presented in the drawings are enlarged or reduced or simplified for ease of description, and the drawings and their components are not necessarily drawn to scale. However, those skilled in the art will readily understand these details.

1 is an exemplary view showing a structure of a 3D printing apparatus having a safety device for laser emission according to the present invention.

Referring to FIG. 1, the 3D printing apparatus according to the present invention includes a table 10, a beam supply unit 20, and a control unit 30.

The table 10 is formed of a material by supply of a material material for the formation of the material and the material material. To this end, the table 10 includes a molding part 110 that provides a working space in which a molding material is formed, a material material supply part 120 that supplies material materials to the molding part 110, and the material material remaining after forming the molding material is recovered. The material material receiving unit 130 and the material material accommodated are transferred from the material material supply unit 120 to the molding unit 110 or the material material receiving unit 130 from the molding unit 110, and the molding unit 110 is transferred. It comprises a material material transfer unit 140 to form a material material layer on the.

More specifically, the molding unit 110 is provided with a molding support 111 that can be moved up and down or horizontally. The sculpture supporter 111 serves as a support for the formation of the sculpture, and as the formation of the sculpture progresses, ascends or descends or moves horizontally to assist in forming the sculpture. To this end, a material material layer (not shown) is formed by the material material transfer unit 140 on the sculpture support 111, and a molding layer is formed by supplying a beam from the beam supply unit 20 to the material material layer. The formation of the material material layer and the supply of the beam are repeated on this molding layer, thereby forming a molding. The molding unit 110 may include a frame 112 for guiding the movement of the molding support 111 and a moving means 113 for moving the molding support 111. Particularly, in FIG. 1, a box-shaped frame and a shaft structure for lifting or descending are illustrated as an example, but this is only presented as an example and is not intended to limit the present invention only as shown.

The material material supply unit 120 serves to supply the material material stored in the molding unit 110 for storing the material material for forming the sculpture. The material material supply unit 120 is formed in a container shape to allow the material material to be stored, and also serves to supply the received material material to the molding unit 110 in a constant amount. To this end, the material material supply unit 120 changes the volume of the container so that the material material is constantly discharged, and the material material supply unit 120 supplies the discharged material material to the molding unit 110.

To this end, the material material supply unit 120 moves the inner frame 125 and the inner frame 125 to form a space for accommodating the material material together with the outer frame 127 and the outer frame 127, thereby It may be configured to include a moving means 123 to change the size.

The material material accommodating part 130 serves to receive and store the remaining material material supplied to the molding part 110 by the material material conveying part 140. To this end, the material material receiving unit 130 is disposed at the end of the moving direction of the material material transferring unit 140. For example, as shown in FIG. 1, the material material accommodating part 130 and the material material supply part 120 are arranged in a row with the molding part 110 therebetween, and may be arranged in a line. However, this arrangement corresponds to a case where the material material transfer unit 140 supplies the material material by reciprocating in a straight line, and the movement direction of the material material transfer unit 140 is changed, or the arrangement is changed when the supply method is different. You can.

On the other hand, the material material receiving unit 130 may be configured to include an inner frame and moving means for moving it to change the volume of the receiving space as the amount of material material supplied increases. Alternatively, the present invention is not limited by the suggestion that it may be composed only of a frame having a fixed volume of a predetermined size. Here, when the material material receiving unit 130 is to change the volume of the material material supply unit 120, it is configured in the same form as each other, and the material material supply and reception may be alternately performed.

The material material transfer unit 140 transfers the material material of the material material supply unit 120 onto the molding supporter 111 of the molding unit 110, and also forms a material material layer on the molding material supporter 111. In addition, the material material transfer unit 140 serves to transfer material materials that are not used to form the molding layer to the material material receiving unit 130. To this end, the material material transfer unit 140 reciprocates along the material material supply unit 110, the molding unit 120, and the material material receiving unit 130 to supply the material material, form the material material layer, and recover the remaining material material Is done.

The material material transfer unit 140 is moved on the material material supply unit 110, the molding unit 120 and the material material receiving unit 130 by a transport means (not shown), supplying and recovering the material material and recovering the material material layer. To form. Particularly, in order to facilitate the formation of the material material layer when supplying the material material, the material material transfer unit 140 may include a blade 141 or a roller (not shown), but only by limiting the present invention no. The blade 141 is formed in a plate shape and transports the material material by a blade portion in contact with the material material, and is planarized. Here, the blade 141 and the roller may be provided together to assist the formation of the material material layer by the roller, and in addition to the proposed blade 141, the roller, the material material in powder or mucus state can be transported or formed in a thin layer. Any device can be modified or added to the configuration.

The beam supply unit 20 supplies a laser beam to the material material layer formed on the molding unit 110 to form a molding layer having a predetermined shape. Here, the material material is a material for forming a molded material, such as synthetic resin, glass, metal, ceramic, etc., which reacts to heat or light to induce a reaction in which a material whose physical properties are changed into a powder or particle form or a liquid state or induce a reaction. It may be prepared by mixing with an inducer for. In one example, the material material may be temporarily melted by heat or energy supplied by a beam and then cured to form a molded layer, and a photosensitive powder, for example, a powder material that is cured by ultraviolet light may be used. It is also possible to form a molding layer.

To this end, the beam supply unit 20 forms a molding layer by supplying light having a predetermined wavelength according to the type of material material, or by supplying heat or energy to change a state of a part of the material material layer.

The beam supply unit 20 receives the beam from the laser unit 121 and the laser unit 121 that generate a beam according to the control signal of the control unit 30 to the table surface layer of the forming unit 110, that is, the material material layer It may be configured to include a scan head 124 for irradiating the beam. Here, in order to supply a beam from the laser unit 121 to the scan head 124, a beam transmitting member such as an optical fiber 122 may be provided to each other, but the present invention is not limited thereto. The laser unit 121 generates a beam by a control signal supplied from the control unit 30.

The scan head 124 forms a molding layer by changing the state of the material material by irradiating a beam supplied from the laser unit 121 to the material material layer formed on the molding supporter 111 of the molding unit 110. In particular, the scan head 124 changes the irradiation position of the beam under the control of the control unit 30 to form a pre-determined molding layer.

The control unit 30 controls the driving of the beam supply unit 20 and the table 10, generates control signals for controlling them, and supplies them to each of the beam supply unit 20 and the table 10.

In particular, the control unit 30 supplies a control signal for controlling beam generation and beam output intensity by the beam supply unit 20 and a coordinate signal for controlling a region where the beam is irradiated, and irradiated by the scan head 124 In addition to determining the position, beam emission at the irradiation position is controlled.

In this process, the control unit 30 compares the detection result supplied from the detection means 130 and the control signal to detect the normal emission of the laser beam, and determines whether a malfunction has occurred. This will be described in more detail with reference to FIG. 2 below.

2 is an exemplary view showing a configuration for error detection of a 3D printing apparatus according to the present invention.

1 and 2, the control unit 30 includes a sensor 132, a control signal generator 131, a detection means 133 and a detection unit 135.

The control unit 30 forms a composition layer by controlling the emission and irradiation position of the laser beam as described above, and accordingly, the laser unit 121 and the scan head to supply, recover, and form the material layer. The 124 and the table 10 are controlled to form a 3D sculpture as a result.

In this process, the control unit 30 detects an operation state such as normal emission of the laser beam and determines whether there is an abnormality accordingly.

Specifically, the control signal generator 131 generates control signals (first and second signals) that cause the laser unit 121 to generate a beam, and transmits the generated signals to the laser unit 121.

At this time, the light emission control signal for controlling beam generation and beam generation stop (here, assumed as a second signal) is relayed by the detection means 133 and transmitted to the laser unit 121.

The laser unit 121 intermittently generates the laser beam 126 by the control signal transmitted from the control signal generator 131 and transmits it to the scan head 124. Here, the control signal may be a plurality of signals (first and second signals) as illustrated in the drawing. In FIG. 2, although an example is shown in which the control signal is composed of two signals, the first signal and the second signal, the present invention is not limited by the suggestion that the control signal may be composed of only one or more signals. For example, the first signal may be a current signal for adjusting the intensity of the beam 126, and the second signal may be a voltage signal for controlling the emission or stoppage of the beam.

The sensing means 133 relays a signal for controlling light emission (on / off) among control signals transmitted to the laser unit 121 and transmits the signal to the laser unit 121. Then, the beam emission is detected from the scan head 124 and the detection result and the control signal are transmitted to the detection unit 135.

More specifically, the sensing means 133 is provided with a sensor 132 for directly checking whether a beam is emitted from the scan head 124 to the molding support 113 of the forming unit 110, and is provided by the sensor 132. When the beam 126 emission is detected, the detection result is transmitted to the detection means 133. Here, the sensor 132 may be configured as a sensor capable of detecting the beam 126, such as a photo sensor, or a sensor of the same type. The sensor 132 may be configured with one sensor 132 on the path of the beam when the distance between the scan head 124 and the forming unit 110 is close. Alternatively, when the distance between the scan head 124 and the forming part 110 is long, a plurality of beam output nozzles of the scan head 124 and the molding support 113 of the forming part 110 may be respectively provided. That is, it is possible to detect whether the beam emission is made from the scan head 124 and whether the emitted beam normally reaches the sculpture support. In addition, when the laser unit 121 and the scan head 124 are separated and the beam is transmitted by a relay means such as an optical fiber 122, a sensor 132 may be installed at the beam output terminal of the laser unit 121.

The detection means 133 combines the control signal and the beam detection result and transmits it to the detection unit 135. Particularly, when the second signal, which is an on / off control signal, is transmitted from the control signal generator 131, the detection means 133 synchronizes the detection result transmitted from the second signal and the sensor 132 to the detection unit 135. Will be delivered.

When the second signal and the detection result are collected and transmitted from the detection means 133, the detection unit 135 compares the second signal with the detection result to determine whether emission of the beam 126 was made during the on period of the second signal. It is determined whether the emission of the beam 126 is stopped during the off period of the second signal. In addition, the detection unit 135 determines whether the emission of the beam according to the second signal is performed within a predetermined delay time.

Through this, the detection unit 135 determines whether emission of the beam 126 deviated from the on / off period has occurred, emission of the beam 126 has not occurred, or a specified delay time has elapsed.

The sensing means 133 may adjust the intensity of the beam sensed by the sensor 132 according to the type, type, or working environment in which the material material is printed. In addition, the detection means 133 may adjust the time for detecting the beam detection of the sensor 132.

Specifically, a composition layer may be formed when a material material is irradiated for a long time or a strong beam, or a composition layer may be sufficiently formed even when a weak beam is irradiated. In addition, there may be various environmental conditions, such as when the working environment is bright, dark, when there is a large amount of airborne suspended matter or moisture such as dust.

In this way, the intensity of the beam generated in the laser unit 121 may be changed according to the environmental conditions or the type and state of material materials. Further, even if the same beam is emitted according to environmental conditions, the recognition by the sensor 132 may be different.

In preparation for this case, the sensing means 133 is provided to adjust the intensity of the beam recognized by the sensor 132 and the time required for it. The detection intensity and the detection recognition condition may be set by the user, or it may be possible for the detection means to automatically change the setting according to pre-entered environmental information or material material information.

In addition, the detection means 133 may be configured to include an amplification device for adjusting the intensity for adjusting the detection intensity. That is, the intensity control amplifying device may be provided in the sensing means 133 to amplify the signal of the weak sensitivity and reduce the signal of the strong sensitivity to be transmitted.

3 is an exemplary configuration diagram showing a configuration for error detection of a 3D printing apparatus according to a second embodiment of the present invention.

Referring to FIG. 3, the 3D printing apparatus according to the second embodiment has substantially the same configuration as the first embodiment of FIG. 2 described above, but has a difference from the first embodiment in the sensing means 233.

Specifically, the sensing means 233 of the second embodiment relays and transmits all signals transmitted from the control signal generator 131 to the laser unit 121, unlike the sensing means 133 of the first embodiment. That is, the sensing means 233 does not transmit only the second signal, which is an on / off signal, to the laser unit 121, but transmits the first signal together with the second signal to the laser unit 121.

This second embodiment can be used when synchronization of the first signal and the second signal is necessary, such as a signal that controls the intensity of the beam 126 during the second signal on / off signal and the first signal on. Can be.

That is, when the sensing means 133 relays only the first signal in a situation where synchronization of the first signal and the second signal is necessary, synchronization between the second signal and the first signal via the sensing means 133 may be misaligned. Therefore, the sensing means 233 relays the second signal and the first signal together, and in particular, delays and transmits the first signal by a time delay generated by relaying the second signal. To this end, the sensing means 233 may be provided with means for delaying the first signal.

On the other hand, Figure 4 is an exemplary view showing the configuration of a conventional 3D printing apparatus, Figure 5 is an exemplary view showing an example for explaining the abnormality determination process of the detection unit in the form of a table.

The conventional 3D printing device is not provided with a sensing means 133 as shown. In the conventional 3D printing apparatus, when the first and second signals are transmitted from the control signal generator 331 to the laser unit 321, the laser unit 321 generates a laser according to the first and second signals to generate a scan head ( 324), and the scan head 324 irradiates the laser in the form of a beam.

Such a 3D printing device needs to generate and irradiate a beam for a long time in order to generate a sculpture, and as the working time increases, a malfunction occurs, and although the control signals (first and second signals) are transmitted, the beam is generated and emitted. There is a case in which it is not supported, a control signal is not transmitted, or a beam is emitted in an off-signal section.

However, in the conventional 3D printing apparatus, such a malfunction can be known only by checking the state of the sculpture. On the other hand, in the present invention, it is possible to quickly check whether an abnormality has been generated and to respond to a failure, because it is possible to check whether the laser is generated and the beam is emitted in response to the control signal using a sensor and a sensing means.

Specifically, as illustrated in FIG. 5, the detection unit may determine the abnormality.

In FIG. 5, the second signal is illustrated as being divided into on / off to facilitate understanding, but may be a continuous signal in which the voltage level fluctuates (high & low).

The detection result shows the result of sensing the actual emission of the beam through the sensor 132, and is indicated as "O" when there is beam emission and "X" when there is no beam emission.

First, the detection unit 135 may perform the same determination as the first determination result based only on whether the second signal is on / off and the detection result of beam emission. In more detail, the detection unit 135 determines that the second signal is transmitted to the detection means 133 (on), and if it is determined that the beam is detected by the sensor 132, it is determined as normal. Similarly, if the second signal is not transmitted to the detection means 133 or the off signal is transmitted as the second signal, the detector 135 determines the normal off state. .

However, the detection unit 135 does not detect the beam by the sensor 132 when the second signal is on or the beam is detected by the sensor 132 when the off signal is transmitted as the second signal. If it is, it is judged as "malfunction" or "abnormality".

In addition, as described above, the detection unit 135 may include the delay period in determining normal and malfunction.

That is, even if it is determined that the first determination result is normal, the detection unit 135 determines that the beam is detected as a malfunction or abnormality when a beam is detected exceeding a predetermined delay time after the second signal is transmitted. Then, the operation is stopped according to the determination result, and the failure is transmitted so that the user can respond to the failure through an alarm or notification. On the other hand, the detection unit 135 is determined to be normal in the first determination result, and if the beam is detected within the delay time after the second signal is transmitted, it is determined that the operation is finally normal, thereby controlling the printing device to continue the operation.

As described above, the present invention detects a beam emission error, which is the most important error in 3D printing, by using whether or not a signal is transmitted, a beam is generated, and a delay time, unlike a conventional 3D printing device, and thus proceeds or stops work Will perform. Through this, it is possible to minimize the hassle of discarding or correcting the pre-worked sculptures by stopping the work at the moment of the abnormality by preventing the work sheet from progressing even in the situation where the abnormality has occurred.

In particular, by improving the reliability of the device by implementing a simple configuration consisting of a sensing means and a sensor, it is possible to improve the reliability without increasing the complexity of the 3D printing device.

In the above, although illustrated and described as a specific example to illustrate the technical spirit of the present invention, the present invention is not limited to the same configuration and operation as the specific embodiment as described above, and various modifications are within the limits of the present invention. Can be conducted at Therefore, such variations should also be regarded as belonging to the scope of the present invention, and the scope of the present invention should be determined by the claims below.

10: table 110: forming part
111: sculpture support 112: frame
113: moving means 120: material material supply unit
121, 321: laser unit 122: optical fiber
123, 324: scan head 130: material material receiving unit
131, 331: control signal generator 132: sensor
133, 233: detection means 135: detection unit
140: material material transfer unit 20: beam supply unit
30: control unit

Claims (6)

A molding part to which a material material for forming a sculpture is supplied;
A beam supply unit for forming a molding layer by supplying a beam to the material material supplied to the molding unit;
A control unit generating a control signal for controlling the supply of the beam;
A signal for controlling light emission among the control signals is transmitted to the beam supply unit, and a sensor is provided to detect whether the beam is emitted from the beam supply unit, and a light detection result is generated using the detection result of the sensor Detecting means; And
And a detector configured to compare the light detection result with the control signal to detect whether the beam is emitted according to the control signal.
The detection means,
The relaying control signal is a signal for controlling on / off of the beam supply unit,
The sensor is installed at least one on the path of the beam between the scan head and the forming part to detect whether the beam is generated in the path,
The on / off control signal of the beam supply unit and the light detection result of the sensor are synchronized and transmitted to the detection unit,
The detection unit,
It is detected whether or not the beam is emitted according to the control signal,
If there is no emission of the beam in the on signal of the beam supply unit or the emission of the beam in the off signal of the beam supply unit, it is determined as abnormal.
3D printing device. delete According to claim 1,
The control signal is a 3D printing device, characterized in that a voltage signal or a current signal composed of a plurality. delete According to claim 1,
A material material supply unit for receiving the material material and supplying a material material for forming the molding layer;
A material material transfer unit for supplying the material material to the molding unit and forming a material material layer for forming the molding layer;
3D printing apparatus, characterized in that further comprises a; material material receiving portion for receiving the material material remaining after forming the molding layer. According to claim 1,
The sensing means
The detection intensity, which is the time required for the sensor to sense the beam and the time for the sensor to detect the beam, is adjusted,
3D printing device, characterized in that further comprises a control amplifying device for adjusting the detection intensity.

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