Large 3D printer based on FDM principles

[0021] Such as figure 1 The leveling control system mainly includes a distance measuring sensor and a threaded shaft motor. The distance measuring sensor (1) is installed above the working panel (2) to monitor the position of the working panel. The working panel and three threaded shaft motors ( 3) Phase connection, a spring (5) is arranged on the threaded shaft, and three threaded shaft motors are fixedly connected through the base (4).

[0022] The ranging sensor is fixed together with the three-axis motion platform. According to the principle of determining a plane with three points, the test points of the board are arranged in an equilateral triangle, and then the ranging sensor is moved to the three vertices of the equilateral triangle for distance measurement. After starting the leveling program, the CPU gives the distance measuring sensor a working instruction, the distance measuring sensor starts measuring, and then feeds back the distance data to the CPU. The CPU compares the feedback distance data with the preset distance data. If the feedback distance data is more than the preset distance data If the distance data is large, the CPU starts the screw shaft motor to rotate in the positive direction. Because the screw shaft of the motor is screwed to the base, and the motor housing is not allowed to rotate due to the limitation of the base, when the motor shaft rotates in the positive direction, the motor rises and the work panel Ascend, shorten the distance, and the ranging sensor continues to measure the distance until the preset distance is reached. If the feedback distance data is smaller than the preset distance, the measured motor shaft rotates in the reverse direction, the motor goes down, the working panel goes down, and the distance is increased until the preset distance is reached.

[0023] The heat dissipation control system mainly includes the cooling and solidification of motors, nozzles and materials. The current FDM technology cannot print large-size models, which is directly related to the bridge edge problem caused by uneven cooling and solidification of materials. In order to ensure the effectiveness of large-size FDM parts For molding, we use a large-area cooling fan to directly cool the printed model during the printing process, thereby reducing the internal stress of the material and reducing the probability of part warping.

[0024] Such as figure 2 , Large-area fan (6) print model (7), the large-area fan cools the printed model in time during the printing process, the airflow takes away a lot of heat, speeds up the cooling of the model, and evenly cools the printed model , Reduce heat conduction, and realize instant cooling.

[0025] Material suspension system: such as image 3 , The suspension system of the material mainly includes the material support (8), the support rod (9), the material coil (10) and the wire plastic (11). When the material is fed, due to the meshing effect of the feeding mechanism, the material is meshed and moved forward, thereby driving The material roll rotates on the supporting rod (9). This suspension mode ensures that the material directly enters the feeding mechanism, avoids the material from entering the feeding mechanism in other curved ways, greatly reducing the feeding resistance and improving the feeding reliability .

[0026] Process display system: The process display system mainly includes LCD display and corresponding LCD circuit, which can display the printing process and nozzle temperature in time, so that the operator can intuitively understand the speed of model printing and printing time.