阅读说明：本技术 一种3d打印机喷头机构的检测装置及方法 (Detection device and method for 3D printer nozzle mechanism ) 是由 蒋铭波 黄宇立 杨振安 罗小帆 于 2019-12-03 设计创作，主要内容包括：本发明提供了一种3D打印机喷头机构的检测装置及方法,所述检测装置包括但不限于以下部件：挤出系统、压力测试机构、控制系统,所述挤出系统用于将打印线材线材输送、熔融、挤出；所述压力测试机构与挤出系统相连,以测量线材挤出压力；所述控制系统与挤出系统和压力测试机构均相连。采用该装置对喷头机构进行检测,可以不同的打印速度、打印温度、回抽距离等参数进行3D打印线材的熔融挤出,测试并表征挤出压力、出口温度、挤出胀大、喷嘴漏料等挤出行为,对测试数据进行统计分析,可以评估测试线材和喷头机构的适配性,找到线材最佳的使用条件。(The invention provides a detection device and a method for a 3D printer nozzle mechanism, wherein the detection device comprises but is not limited to the following components: the system comprises an extrusion system, a pressure testing mechanism and a control system, wherein the extrusion system is used for conveying, melting and extruding printing wire rods; the pressure testing mechanism is connected with the extrusion system to measure the extrusion pressure of the wire; and the control system is connected with the extrusion system and the pressure testing mechanism. Adopt the device to detect shower nozzle mechanism, printing speed that can be different, printing temperature, pumpback distance isoparametric carry out the melting of 3D printing wire rod and extrude, test and the expression extrusion pressure, exit temperature, extrude the action of extruding such as bloated, nozzle hourglass material, carry out statistical analysis to test data, can evaluate the suitability of test wire rod and shower nozzle mechanism, find the best service condition of wire rod.)

1. The utility model provides a detection device of 3D print head mechanism which characterized in that includes:

an extrusion system for conveying, melting, extruding a printing wire (9);

the pressure testing mechanism is connected with the extrusion system and used for supporting the extrusion system so as to measure the extrusion pressure of the wire rod;

and the control system is connected with the extrusion system and the pressure testing mechanism.

2. The detection device of a 3D printer head mechanism according to claim 1, characterized in that the extrusion system comprises a wire feeding mechanism (11) which feeds a printing wire (9) to a pressure testing mechanism.

3. The detection device of the 3D printer nozzle mechanism according to claim 2, wherein the wire conveying mechanism (11) is one or more of a motion mechanism comprising gears, shafts, belts, rollers and motors; the motor is connected with the control system.

4. The detection device of a 3D printer head mechanism according to claim 2 or 3, characterized in that the extrusion system further comprises a wire heating mechanism (13), the wire heating mechanism comprises a nozzle (12), a heating block and a thermocouple, a heating rod and a temperature controller connected with the control system, the heating block is positioned outside the nozzle and is used for heating and melting the printing wire (9).

5. The detection device of the 3D printer nozzle mechanism according to claim 4, wherein the wire heating mechanism (13) is located below the wire conveying mechanism (11) and is used for receiving the printing wire (9) conveyed by the wire conveying mechanism (11).

6. The detection device and method for the 3D printer nozzle mechanism according to claim 5, characterized in that the extrusion system further comprises a metering mechanism () connected with the control system, the metering mechanism is arranged above the wire conveying mechanism (11) and is used for measuring the moving length of the printing wire (9).

7. The detecting device for the 3D printer nozzle mechanism according to claim 6, wherein the meter mechanism is an electronic meter.

8. The detecting device for the 3D printer nozzle mechanism according to any one of claims 5 to 7, characterized by further comprising an optical imaging system (6) connected with the control system.

9. The detecting device for the 3D printer nozzle mechanism according to claim 8, characterized in that the optical imaging system is a visible light imaging system or/and an infrared light imaging system, which is adjacent to the nozzle (12) to photograph the outlet of the nozzle.

10. The detection device for the 3D printer nozzle mechanism according to claim 9, further comprising a nozzle wiping mechanism (2) connected to the control system, wherein the nozzle wiping mechanism is adjacent to the nozzle (12) and is used for wiping the outlet of the nozzle.

11. The detection device for the 3D printer nozzle mechanism according to claim 5, wherein the nozzle wiping mechanism (2) comprises a stepping motor (24) and a nozzle wiping block (22), and the stepping motor drives the nozzle wiping block to rotate back and forth to enable the nozzle wiping block to wipe the nozzle (12); the stepping motor is connected with the control system.

12. The detecting device for the 3D printer nozzle mechanism according to claim 10, wherein the pressure testing mechanism comprises at least one pull pressure sensor (41), a pull pressure sensor meter (4) connected with the pull pressure sensor and used for reading a pressure value; wherein one end of the tension and pressure sensor (41) is fixed, and the other end is suspended to support the wire heating mechanism (13); the pressure sensor and the pull pressure sensor instrument are connected with the control system.

13. The detecting device for the 3D printer nozzle mechanism according to claim 12, wherein the pulling and pressing force sensor (41) includes but is not limited to an S-shaped pulling and pressing force sensor, an L-shaped high pulling and pressing force sensor, and a U-shaped pulling and pressing force sensor.

14. The detection device of the 3D printer nozzle mechanism according to claim 13, wherein the wire conveying mechanism (11) is located above the tension and pressure sensor (41), and a pipeline for the printing wire (9) to pass through is arranged on the wire conveying mechanism.

15. The detection device for the 3D printer nozzle mechanism according to claim 14, wherein a conveying pipeline coaxial with the pipeline in the wire conveying mechanism (11) is arranged in the wire heater component (13), and the distance between the two pipelines is not more than 10 mm; when the size of the wire is 1.75mm, the inner diameters of the two pipelines are 1.75 mm-2.5 mm; when the size of the wire is 2.85mm, the inner diameters of the two pipelines are 2.85 mm-3.5 mm.

16. The method for detecting the mechanism parameters of the 3D printer nozzle by using the device of claim 15, which is characterized by comprising the following steps:

A. installing a detection device, starting up the machine for preheating, and inserting the 3D printing wire rod into the wire rod mechanism (13) after penetrating through the metering mechanism;

B. starting the device to melt and extrude the wire;

C. the extrusion behaviour of the material on the equipment was tested and characterised.

17. The assay of claim 16, wherein the extrusion behavior comprises one or more of extrusion pressure, die swell, exit temperature, and nozzle blowby.

18. The detection method according to claim 17, comprising the steps of:

A. manually enabling the printing wire to pass through the metering mechanism and be inserted into the wire conveying mechanism; when the printing wire moves, a wheel on the metering mechanism is driven to rotate, and the mechanism records the actual length of the conveyed wire;

B. the wire conveying mechanism conveys the wires into the wire heating mechanism, and the wires are extruded from the outlet of the nozzle after being heated and melted by the wire heating mechanism; in the process, the wire can press the nozzle downwards, so that the tension pressure sensor works to measure the extrusion pressure;

C. in the stable extrusion process, the wires are extruded into thinner filiform wires at the nozzle; and shooting the extruded material through an optical image system to obtain a visible light image of the extrusion swelling and nozzle leakage behavior and an infrared light image of the outlet temperature.

Technical Field

The invention relates to the technical field of 3D printing, in particular to a detection device and a detection method for a 3D printer nozzle mechanism.

Background

Fused Deposition manufacturing (fdm) is a common 3D printing technique, and the material is generally a thermoplastic material, such as PLA, ABS, nylon, etc., and is fed in a linear form, and the material is heated and melted in a nozzle. The spray head moves along the section contour and the filling track of the part, and simultaneously extrudes the molten material, and the material is rapidly solidified and coagulated with the surrounding material.

The material is the core of the 3D printing technology, the spray head is the core component of the FDM type 3D printer, the printing temperature and the printing speed are the core parameters of the material working on the printer, but no mature equipment and method can rapidly test the material and the spray head structure to verify whether the parameters are matched at the present stage. Generally, a specific model can be printed only through actual 3D, and then feedback is carried out according to the printing quality of the model, interference factors are excessive in the process, and the test period is long.

Disclosure of Invention

The invention aims to provide a detection device and a detection method for a 3D printer nozzle mechanism, which can realize the aspects that the existing equipment cannot be tested, including the measurement of wire extrusion pressure, the measurement of the temperature at the moment when a material is extruded from a nozzle, the measurement of extrusion swelling when the material is extruded from the nozzle, and the measurement of nozzle flash after the extrusion of the material from the nozzle is stopped.

The invention is realized by the following steps:

a detection device of 3D print head mechanism includes:

the extrusion system is used for conveying, melting and extruding the printing wire rods;

the pressure testing mechanism is connected with the extrusion system and used for supporting the extrusion system so as to measure the extrusion pressure of the wire rod;

and the control system is connected with the extrusion system and the pressure testing mechanism.

Preferably, the extrusion system comprises a wire conveying mechanism, and the wire conveying mechanism is used for conveying printing wires.

In detail, the wire conveying mechanism is one or more of a motion mechanism comprising a gear, a shaft, a belt, a roller and a motor; the motor is connected with the control system.

In detail, the extrusion system further comprises a wire heating mechanism, the wire heating mechanism comprises a nozzle and a heating block connected with the control system, and the heating block is positioned outside the nozzle and used for heating and melting the printing wire; the wire heating mechanism is positioned below the wire conveying mechanism and used for receiving the printing wires conveyed by the wire conveying mechanism.

More specifically, the wire heating mechanism further comprises a thermocouple, a heating rod and a temperature controller which are connected with the control system, and the thermocouple and the heating rod are arranged on the heating rod and connected with the temperature controller.

Furthermore, the extrusion system further comprises a meter counting mechanism connected with the control system, and the meter counting mechanism is arranged above the wire conveying mechanism and used for measuring the moving length of the printing wire.

Further, the meter mechanism is an electronic meter.

Furthermore, the detection device also comprises an optical image system connected with the control system.

Preferably, the optical imaging system is a visible light imaging system or/and an infrared light imaging system, which is adjacent to the nozzle to photograph the outlet of the nozzle.

Preferably, the device also comprises a nozzle wiping mechanism connected with the control system, wherein the nozzle wiping mechanism is adjacent to the nozzle and used for wiping the outlet of the nozzle.

As a preferred scheme, the nozzle wiping mechanism comprises a stepping motor and a nozzle wiping block, wherein the stepping motor drives the nozzle wiping block to rotate in a reciprocating manner, so that the nozzle is quickly wiped by the nozzle wiping block; the stepping motor is connected with the control system.

As a preferable scheme, the pressure testing mechanism comprises at least one pull pressure sensor, a pull pressure sensor instrument which is connected with all the pull pressure sensors and is used for reading pressure values; one end of the pull pressure sensor is fixed, and the other end of the pull pressure sensor is suspended to support the nozzle; the pressure sensor and the pull pressure sensor instrument are connected with the control system.

Preferably, the pull pressure sensor includes, but is not limited to, an S-type pull pressure sensor, an L-type pull pressure sensor, and a U-type pull pressure sensor.

As a preferable scheme, the wire conveying mechanism is located above the tension and pressure sensor, and a pipeline for the printing wire to pass through is arranged on the wire conveying mechanism.

As a preferable scheme, a conveying pipeline which is coaxial with the pipeline in the wire rod conveying mechanism is arranged in the wire rod heating mechanism, and the distance between the two pipelines is not more than 10 mm; when the size of the wire is 1.75mm, the inner diameters of the two pipelines are 1.75 mm-2.5 mm; when the size of the wire is 2.85mm, the inner diameters of the two pipelines are 2.85 mm-3.5 mm.

Meanwhile, the invention also provides a method for detecting the 3D printer nozzle mechanism by using the detection device.

The method is realized by the following steps:

a method for detecting 3D printer nozzle mechanism parameters by using the device comprises the following steps:

A. installing a detection device, preheating, and inserting the 3D printing wire into a nozzle after passing through a pipeline of a wire conveying mechanism;

B. starting the device to melt and extrude the wire;

C. the extrusion behaviour of the material on the equipment was tested and characterised.

Preferably, the extrusion behavior comprises one or more of extrusion pressure, die swell, exit temperature and nozzle blowby.

In detail, the method specifically comprises the following steps:

A. manually enabling the printing wire to pass through the metering mechanism and be inserted into the wire conveying mechanism; when the printing wire moves, a wheel on the metering mechanism is driven to rotate, and the mechanism records the actual length of the conveyed wire;

B. the wire conveying mechanism conveys the wires into the nozzle, and the wires are extruded from the outlet of the nozzle after being heated and melted by the wire heating mechanism; in the process, the wire can press the nozzle downwards, so that the tension pressure sensor works to measure the extrusion pressure;

C. in the stable extrusion process, the wires are extruded into thinner filiform wires at the nozzle; shooting the extruded material through an optical imaging system to obtain images of extrusion swelling and nozzle leakage;

D. during stable extrusion, the infrared imaging system measures the exit temperature of the material immediately after extrusion at the nozzle.

The method and the principle for detecting the parameters of the extruding mechanism of the 3D printer by adopting the detection device are as follows:

1. the wire rod is manually inserted into the wire rod conveying mechanism after passing through the metering mechanism. The wire is moved to rotate a wheel on a metering mechanism which records the actual length of the wire as it is conveyed.

2. The control system controls the wire rod conveying mechanism, the conveying wire rods enter the wire rod heating mechanism, and the wire rods are extruded out from the nozzle after being heated and melted in the wire rod heating mechanism. In the process, the wire presses the nozzle downwards, the pressure is transmitted to a pressure testing mechanism, and the measured pressure is the extrusion pressure of the wire.

3. In the stable extrusion process, the strand is extruded into a thinner filamentous strand at the nozzle, and due to the characteristics of the polymer material, when some materials are melt-extruded through a small hole, the size of the extruded strand is generally larger than that of the small hole, which shows that the diameter of the filamentous strand is larger than the inner diameter of the nozzle outlet, which is the 'extrusion swelling' behavior.

4. And at a certain set moment, the control system controls the nozzle wiping mechanism to clear the material extruded from the nozzle, and the wire conveying mechanism stops conveying.

5. The wire rod staying in the wire rod heating mechanism is reduced in viscosity and even degraded due to the continuous heating effect, and the material can leak from the nozzle due to the multiple influences of factors such as thermal expansion, gravity action and the like of the material, so that the action of 'nozzle leakage' is realized.

6. In the whole test process, the optical image system records the visible light image and the infrared light image of the nozzle area.

7. The visible light image is processed by software. 1) The diameter of the wire in the "die swell" behavior was measured and used to characterize the extent of "die swell". 2) The time from the start of the removal of the material extruded at the nozzle to the occurrence of the "nozzle bleed" behavior in the "nozzle bleed" behavior was measured and the extent of the "nozzle bleed" was characterized by the period of no bleed time.

8. The infrared light effect was processed with software to measure the actual temperature of the material immediately after it was extruded at the nozzle. This is the "outlet temperature".

9. And (4) carrying out statistical analysis on the measured extrusion pressure, the measured extrusion swelling degree, the measured nozzle leakage degree and the measured outlet temperature to evaluate whether the wire rod and the sprayer mechanism are matched or not.

The invention has the beneficial effects that:

(1) the detection device and the method can realize the aspect that the existing equipment can not be tested, such as the measurement of the extrusion pressure of the wire rod by a pressure testing mechanism, the measurement of the instantaneous temperature of the extrusion of the material from the nozzle by an infrared image system, and the measurement of the extrusion swelling of the material when the material is extruded from the nozzle and the measurement of the nozzle flash after the extrusion from the nozzle is stopped by an optical image system.

(2) The device can be used for monitoring and recording data such as printing temperature, extrusion pressure, flow, material extrusion instant temperature and the like on line to reflect the extrusion condition of the wire. Such as: the wire rod is extruded on this device, can test the pressure of extruding, line footpath data in the extrusion process. After the data are subjected to statistical analysis, whether the current temperature and speed are suitable for the material can be evaluated, and the most suitable printing temperature and printing speed of a certain material can be judged by adjusting the temperature and the extrusion speed of the wire conveying mechanism, so that the testing efficiency is higher compared with the traditional method.

(3) By analyzing the data obtained by the measurement of the device, feedback can be provided for the design of the spray head, and a 3D printer manufacturer can be guided to design the spray head mechanism.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a schematic view of the installation of the spray head mechanism of the present invention;

FIG. 3 is a detail view of the installation of the spray head mechanism of the present invention;

fig. 4 is a schematic structural diagram of the nozzle wiping mechanism of the spray head of the invention.

Icon:

1-spray head mechanism, 11-wire rod conveying mechanism, 12-spray nozzle, 13-wire rod heating mechanism, 14-wire rod heating mechanism fixing beam, 15-spray nozzle fixing plate, 2-spray head wiping nozzle mechanism, 21-wiping nozzle mechanism mounting table, 22-spray head wiping block, 23-stepping motor mounting seat, 24-stepping motor, 3-instrument table frame, 4-pulling pressure sensor instrument, 5-temperature controller, 51-heating block, 52-heating rod, 53-thermocouple, 6-optical imaging system, 7-processor, 8-spray head mounting plate and 9-printing wire rod.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings of the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

In the description of the present invention, it is to be understood that the terms indicating an orientation or positional relationship are based on the orientation or positional relationship shown in the drawings only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings or the orientations or positional relationships that the products of the present invention are conventionally placed in use, and are only used for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance.

Furthermore, the terms "horizontal", "vertical", "overhang" and the like do not imply that the components are required to be absolutely horizontal or overhang, but may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

In the present invention, unless otherwise expressly stated or limited, the first feature may be present on or under the second feature in direct contact with the first and second feature, or may be present in the first and second feature not in direct contact but in contact with another feature between them. Also, the first feature being above, on or above the second feature includes the first feature being directly above and obliquely above the second feature, or merely means that the first feature is at a higher level than the second feature. A first feature that underlies, and underlies a second feature includes a first feature that is directly under and obliquely under a second feature, or simply means that the first feature is at a lesser level than the second feature.