阅读说明：本技术 粉末流量检测装置及方法 (Powder flow detection device and method ) 是由 王旭琴 赵凯 杜洋 刘正武 孙靖 邓文敬 王毅 于 2020-12-04 设计创作，主要内容包括：本发明提供了一种粉末流量检测装置及方法,包括：送粉器(1)、送粉管(2)、激光器(3)、光传输通道(4)、方管(5)、光学探测器(6)以及光学头(7)；所述送粉器(1)与送粉管(2)相连；所述送粉管(2)与方管(5)相连；所述方管(5)与光传输通道(4)相连；所述光传输通道(4)与激光器(3)相连；所述光传输通道(4)与光学探测器(6)相连；所述光学头(7)与光传输通道(4)相连。本发明能够检测增材制造设备加工过程中粉末流量,通过量化粉末流量参数,提高设备加工稳定性和质量。(The invention provides a powder flow detection device and a method, comprising the following steps: the device comprises a powder feeder (1), a powder feeding pipe (2), a laser (3), an optical transmission channel (4), a square pipe (5), an optical detector (6) and an optical head (7); the powder feeder (1) is connected with the powder feeding pipe (2); the powder feeding pipe (2) is connected with the square pipe (5); the square tube (5) is connected with the optical transmission channel (4); the optical transmission channel (4) is connected with the laser (3); the optical transmission channel (4) is connected with an optical detector (6); the optical head (7) is connected with the optical transmission channel (4). The invention can detect the powder flow in the machining process of the additive manufacturing equipment, and improves the machining stability and quality of the equipment by quantifying the powder flow parameters.)

1. A powder flow rate detecting device, comprising: the device comprises a powder feeder (1), a powder feeding pipe (2), a laser (3), an optical transmission channel (4), a square pipe (5), an optical detector (6) and an optical head (7);

the powder feeder (1) is connected with the powder feeding pipe (2);

the powder feeding pipe (2) is connected with the square pipe (5);

the square tube (5) is connected with the optical transmission channel (4);

the optical transmission channel (4) is connected with the laser (3);

the optical transmission channel (4) is connected with an optical detector (6);

the optical head (7) is connected with the optical transmission channel (4).

2. The powder flow rate detecting device according to claim 1, further comprising: IPC industrial personal computer;

the IPC industrial personal computer is connected with the powder feeding pipe (2); the IPC industrial personal computer is connected with the powder feeder (1);

the IPC industrial personal computer is connected with the laser (3);

the IPC industrial personal computer is connected with the optical detector (6).

3. The powder flow detecting device according to claim 1, wherein the powder feeding tube (2) is a PVC powder feeding tube.

4. The powder flow detecting device according to claim 1, wherein the square tube (5) is a plexiglas square tube; the light transmittance of the square tube (5) at the wavelength corresponding to the window of the laser (3) reaches 90%.

5. A powder flow rate detection method characterized by using the powder flow rate detection device according to any one of claims 1 to 4, comprising:

step S1: according to the information of the absorption characteristics of the metal powder processed under the actual working conditions, a laser is adopted to provide any one of the following signals:

-an output signal;

-a laser module wavelength;

optical parameters such as power;

acquiring the light emitting state information of the laser according to the diameter information of the powder feeding pipe under the actual working condition;

step S2: according to the light-emitting state information of the laser, a photoelectric detector is adopted to receive any one of the following information:

-an optical signal after passing through the powder feeding tube;

-photodetector sensitivity parameter information;

-lesion threshold parameter information;

acquiring an output signal of the detector according to the reading interface information of the control unit;

step S3: according to the light emitting state and power of the laser, a focusing mirror and an attenuation sheet are selected and matched;

step S4: reading an output electric signal of the photoelectric detector, analyzing the powder flow under the corresponding electric signal and controlling the powder conveying amount of the powder feeder, and acquiring powder flow information and powder conveying amount information of the powder feeder;

step S5: and acquiring powder flow detection result information according to the powder flow information and the powder conveying amount information of the control powder feeder.

6. The powder flow rate detecting method according to claim 5, wherein the step S3 includes:

step S3.1: the powder conveying pipeline is made of any one of the following materials:

-organic glass;

-quartz glass.

7. The powder flow rate detecting method according to claim 5, wherein the step S5 includes:

and S5.1, controlling the powder conveying amount information of the powder feeder according to the powder flow information.

8. The powder flow rate detecting method according to claim 7, wherein the step S5 includes:

and S5.2, acquiring powder flow detection result information according to the relation curve result information.

9. The powder flow rate detection method according to claim 8, wherein the step S5.2 includes:

and S5.2.1, according to the result information of the relation curve, adjusting the powder feeding amount of the powder feeder in time after the powder feeding amount is found to be changed in the detection process, and obtaining the detection result information of the powder flow.

Technical Field

The invention relates to the technical field of laser powder additive manufacturing, in particular to a powder flow detection device and a powder flow detection method.

Background

The powder feeding amount is an important process parameter in the powder additive manufacturing equipment, and the conditions of insufficient powder residual amount or failure of a powder feeder and the like frequently occur in the long-term working process of the equipment, so that the powder feeding amount of the powder in a working state cannot meet the process requirement, and the printing failure of parts is caused. Meanwhile, the laser powder additive manufacturing equipment needs to calibrate the powder output of the powder feeder irregularly, so that the service efficiency of the equipment is reduced. Therefore, the closed-loop control of the powder output amount by the equipment in the printing process is very critical, the success rate of equipment printing can be effectively improved, and assistance is provided for intelligent manufacturing.

Therefore, in order to monitor the powder feeding amount of the powder additive manufacturing equipment in the working process in real time, the invention provides an optical powder flow detection method and device. A powder flow detection module is additionally arranged on the powder feeder of the device, and the data of the powder output amount can be fed back to the control system. The powder feeding amount of the powder is accurately detected, when the powder feeding amount does not meet the technological requirements, the equipment can stop printing, field workers can timely handle problems, and the equipment is guaranteed to operate efficiently.

Patent document CN107952957A discloses an additive manufacturing system, comprising an additive manufacturing module, the additive manufacturing module has two lateral supports and an additive manufacturing forming cavity between the two lateral supports, the two transverse brackets extend in parallel and are separated by a predetermined distance, the additive manufacturing system further comprises an additive manufacturing device and a longitudinal bracket straddling the two transverse brackets, the longitudinal support is movable relative to the two transverse supports in the direction in which the two transverse supports extend, the additive manufacturing device is coupled with the longitudinal support by a guide device and is movable with the longitudinal support, wherein the additive manufacturing system can comprise a plurality of the additive manufacturing modules, adjacent two of the additive manufacturing modules being joined together by a split connection arrangement. The structure and performance of the patent still leaves room for improvement.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a powder flow detection device and a powder flow detection method.

According to the present invention, there is provided a powder flow rate detection device comprising: the device comprises a powder feeder 1, a powder feeding pipe 2, a laser 3, an optical transmission channel 4, a square pipe 5, an optical detector 6 and an optical head 7;

the powder feeder 1 is connected with the powder feeding pipe 2;

the powder feeding pipe 2 is connected with the square pipe 5;

the square tube 5 is connected with the optical transmission channel 4;

the optical transmission channel 4 is connected with the laser 3;

the optical transmission channel 4 is connected with an optical detector 6;

the optical head 7 is connected to the optical transmission channel 4.

Preferably, the method further comprises the following steps: IPC industrial personal computer;

the IPC industrial personal computer is connected with the powder feeding pipe 2; the IPC industrial personal computer is connected with the powder feeder 1;

the IPC industrial personal computer is connected with the laser 3;

the IPC industrial personal computer is connected with the optical detector 6.

Preferably, the powder feeding pipe 2 is a PVC powder feeding pipe.

Preferably, the square tube 5 is made of organic glass square tube. The light transmittance of the square tube 5 corresponding to the wavelength of the laser 3 reaches 90%, and the square tube is not necessarily an organic glass tube.

According to the powder flow detection method provided by the invention, the powder flow detection device comprises:

step S1: according to the absorption characteristic information of the metal powder processed under the actual working condition, a laser is adopted to provide any one of the following signals for optical detection:

-an output signal;

-a laser module wavelength;

optical parameters such as power;

acquiring the light emitting state information of the laser according to the diameter information of the powder feeding pipe under the actual working condition;

step S2: according to the light-emitting state information of the laser, a photoelectric detector is adopted to receive any one of the following information:

-an optical signal after passing through the powder feeding tube;

-photodetector sensitivity parameter information;

-lesion threshold parameter information;

acquiring an output signal of the detector according to the reading interface information of the control unit;

step S3: according to the light emitting state and power of the laser, a focusing mirror and an attenuation sheet are selected and matched;

step S4: and reading the output electric signal of the photoelectric detector, analyzing the powder flow under the corresponding electric signal and controlling the powder conveying amount of the powder feeder, and acquiring the powder flow information and the powder conveying amount information of the powder feeder.

Step S5: and acquiring powder flow detection result information according to the powder flow information and the powder conveying amount information of the control powder feeder.

Preferably, the step S3 includes:

step S3.1: the powder conveying pipeline is made of any one of the following materials:

-organic glass;

-quartz glass; the light transmittance of the square tube 5 corresponding to the wavelength of the laser 3 reaches 90%, and the square tube is not necessarily an organic glass tube.

The transmission loss of the laser in the light pipeline is reduced to the minimum. The powder content in the working environment of the detection device is high, so that the influence of the environment on the detection is avoided, and the light transmission pipeline has certain tightness.

Preferably, the step S5 includes:

and S5.1, receiving an optical signal output by the laser through the photoelectric detector according to the powder flow information and the powder conveying amount information for controlling the powder feeder, calibrating the change of an electric signal output by the detector under different powder flows according to the change of the optical signal, fitting a relation curve of the electric signal and the powder flow, and obtaining result information of the relation curve.

Preferably, the step S5 includes:

and S5.2, acquiring powder flow detection result information according to the relation curve result information.

Preferably, said step S5.2 comprises:

and S5.2.1, according to the result information of the relation curve, adjusting the powder feeding amount of the powder feeder in time after the powder feeding amount is found to be changed in the detection process, and obtaining the detection result information of the powder flow.

Compared with the prior art, the invention has the following beneficial effects:

1. the powder flow in the machining process of the additive manufacturing equipment can be detected, and the machining stability and quality of the equipment are improved by quantifying the powder flow parameters;

2. the invention has reasonable structure and convenient use, and can overcome the defects of the prior art;

3. the invention can obtain obvious technical effects in the technical field.

Drawings

Other features, objects and advantages of the invention will become more apparent upon reading of the detailed description of non-limiting embodiments with reference to the following drawings:

FIG. 1 is a schematic diagram of an optical path system for flow detection of additive manufacturing powder according to an embodiment of the present invention;

FIG. 2 is a schematic view of an additive manufacturing powder flow rate detection apparatus according to an embodiment of the invention;

fig. 3 is a schematic flow chart of a method for detecting additive manufacturing powder flow according to an embodiment of the present invention.

Detailed Description

The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the invention, but are not intended to limit the invention in any way. It should be noted that it would be obvious to those skilled in the art that various changes and modifications can be made without departing from the spirit of the invention. All falling within the scope of the present invention.

The invention provides a powder flow detection device and a powder flow detection method, which are applicable to the field of optical detection of additive manufacturing equipment, and provide a powder flow detection solution and a powder flow detection device aiming at the problem that the change of powder feeding amount in the equipment forming process cannot be directly observed. The method and the device mainly comprise a laser, a photoelectric detector, a control system and a transmission channel. The laser is used as an emission source, the photoelectric detector is used as a receiver for detecting the change of optical signals of laser passing through the pipeline after the laser passes through the pipeline, and the powder feeding amount of the powder feeder is adjusted through the change of the optical signals detected by the control system. The powder flow detection device can quickly detect the powder feeding amount formed by equipment with high sensitivity, ensures that the equipment operates efficiently, improves the success rate of equipment printing, and provides assistance for the intelligent manufacturing of the traditional additive manufacturing steering.

In the method and the device for monitoring the powder flow parameters in the process of the additive manufacturing equipment, a detector receives light energy output by a semiconductor laser, a relation curve of the light flux and the powder flow is fitted, and the result is fed back to a control system to realize the flow monitoring of the powder.

Preferably, the powder flow rate detection device mainly comprises a laser, a photoelectric detector, a control system and an optical transmission channel. The laser in the device provides an output signal for optical detection, optical parameters such as the wavelength and the power of a laser module are selected according to the absorption characteristics of the processed metal powder under the actual working condition, and the light emitting state of the laser is determined according to the diameter of the powder feeding pipe under the actual working condition.

Preferably, a photodetector in the powder flow detection optical path system is used for receiving an optical signal after passing through the powder feeding tube, main parameters such as sensitivity and damage threshold of the photodetector are determined according to an output optical signal of the laser, and an output signal of the detector also conforms to a reading interface of the control system.

Preferably, the light transmission pipeline in the powder flow detection light path system comprises a powder feeding pipe and a laser transmission pipeline, wherein the powder feeding pipe adopts organic glass or quartz glass with good light transmittance, so that the transmission loss of laser in the light pipeline is reduced to the minimum. The powder content in the working environment of the detection device is high, so that the influence of the environment on the detection is avoided, and the light transmission pipeline has certain tightness. In addition, a focusing mirror and an attenuation sheet are selected according to the light-emitting state and the power of the laser.

Preferably, the control system in the powder flow detection optical path system is integrated in the additive manufacturing equipment, and can read the output electric signal of the photoelectric detector and analyze the powder flow under the corresponding electric signal, and finally can control the powder conveying amount of the powder feeder.

As shown in fig. 2, a powder flow rate detection device according to an embodiment of the present invention is described in detail below.

In the embodiment of the invention, the powder flow detection device mainly comprises a laser, a photoelectric detector, a control system and an optical transmission channel. The device is arranged on a powder feeding pipe section of an optical head of laser cladding equipment, and ensures that the powder feeding amount of a powder outlet part is accurately measured.

In the embodiment of the invention, the wavelength of the semiconductor laser in the powder flow detection device is 650nm, and the light emitting state is a linear shape and covers the side length of the powder feeding pipe.

In the embodiment of the invention, the powder feeding pipe in the optical transmission channel adopts organic glass with 92% light transmittance, and the powder feeding pipe of the organic glass section is sealed with the PVC powder feeding pipe. In addition, the optical transmission path needs a dust-proof sealing design in order to prevent interference with the remaining powder in the air on the optical transmission link.

In the embodiment of the invention, the received signal of the silicon-based photoelectric detector in the powder flow detection device is incident laser energy, and the output signal is current. Because the effective detection area is slightly smaller than the size of the incident linear laser spot, the area of the spot reaching the detection surface is reduced by adding the focusing mirror in the incident light direction of the detector. According to the formulaAndcalculating a detector damage threshold P_maxAnd sensitivity P_minAnd determining whether the power of the selected laser meets the requirement, and if the power of the laser is greater than the damage threshold of the detector, adding a corresponding attenuation sheet in the incident light direction of the detector.

In the embodiment of the invention, the control system in the powder flow detection device is mainly used for controlling the powder feeding amount of the powder feeder, switching on and off the laser and reading and analyzing the light receiving signal of the photoelectric detector. Particularly, the powder feeding amount of the powder feeder is fed back and adjusted through the analyzed data, so that the technological parameters of the laser cladding equipment in the working process are unchanged, and the forming quality and the printing success rate of the equipment are improved.

In the embodiment of the invention, the powder flow detection method is characterized in that the equipment works in an environment filled with powder, the part printing time is long, and workers cannot judge whether the powder feeding amount is changed in the forming process, so that the detection is carried out by means of an optical technical means. The detection flow chart is shown in fig. 3, the optical power output by the semiconductor laser is received through the photoelectric detector, the current change output by the detector under different powder flow rates is calibrated according to the change of the optical power, a relation curve of the current and the powder flow rate is fitted, and the result is fed back to a control system of the device. And then the powder feeding amount of the powder feeder is adjusted in time after the powder feeding amount is found to be changed in the detection process, so that the powder flow is detected.

In the description of the present application, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the present application and simplifying the description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present application.

The foregoing description of specific embodiments of the present invention has been presented. It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes or modifications may be made by one skilled in the art within the scope of the appended claims without departing from the spirit of the invention. The embodiments and features of the embodiments of the present application may be combined with each other arbitrarily without conflict.