[Solution] As we all know, ordinary 3D printers have low accuracy and incomplete printing. How to upgrade to high-precision 3D printers?

Earlier we briefly introduced 3D printers, applications and their classification, so how to have a higher precision 3D printer?

3D printer printing demo

Take a customer’s 3D printer system upgrade plan as an example to introduce the application case.

What the customer wants to do is 3D printing of light-cured ceramics, which has a faster forming speed and gets rid of the constraints of the mold, and does not depend on the complexity of the parts.

Traditional ceramics can only produce products with simple structures and have the disadvantages of high cost and long production cycle. Ceramic 3D printing can just solve the shortcomings of traditional ceramics.

We have upgraded its original printer control system to improve the real-time performance and stability of the equipment.

3D printer structure and working principle

First, let's briefly understand the structure and working principle of the printer.

System structure diagram

The system structure diagram of the printer is shown in the figure above, which can be divided into six organizations:

IPC: Human-computer interaction interface, analyze the three-dimensional model of the object to be printed, and obtain the graphic information of each layer through the slice software.

PLC: Control the operation of various institutions.

Scraper: set up on the guide rails on both sides of the printing material pool, driven by a stepping motor to move back and forth to level the slurry.

Forming table: set above the printing material pool, driven by a servo motor to move up and down, and used as a base for printing and forming.

Light machine: UV generating device, set under the printing material pool to expose the slurry to solidify and shape it.

Automatic door: open and close the printing compartment, connected with grating sensor and hall sensor to prevent the door from being blocked when closing.

3D printing schematic

The working principle of 3D printer:

DLP light-curing ceramic 3D printer equipment contains a tank that can hold resin-used to hold resin that can be cured after being irradiated with a specific wavelength of ultraviolet light.

The light machine is placed under the liquid tank, and its imaging surface is located at the bottom of the tank. Through the control of energy and graphics, a thin layer of resin of a certain thickness and shape can be cured each time (this layer of resin is exactly the same as the cross-sectional shape obtained by cutting before) .

A forming table is set above the trough, and after each cross-section exposure is completed, it is lifted up to a certain height (the height is consistent with the layer thickness), so that the currently cured solid resin is separated from the bottom surface of the trough and bonded to the lifting plate or On the resin layer of one-time molding.

In this way, three-dimensional entities are generated by layer-by-layer exposure and lifting.

System upgrade plan

According to customer needs, the plan shown in the figure below was finally determined.

PLC: Use NiMotion NIMC2000 integrated controller instead of traditional PLC.

The integrated controller integrates the industrial control panel HMI and CODESYS V3 control platform, PLC functions, and motion control functions into the same hardware device.

Support Modbus, CANopen, EtherCAT and other field buses, standard distributed I/O interfaces of Ethernet, CAN, RS485, RS232, 2*USB and 6*DI/2*DO are powerful and cost-effective.

Scraper and automatic door motor: adopt NiMotion integrated stepper motor.

The integrated stepper motor combines the stepper motor and the driver into one, which is small in size, saves installation space, supports CANopen protocol, and makes communication more convenient.

Communication scheme: Communication between IPC and controller is through OPC-UA.

The integrated controller controls two integrated stepper motors and servo motors via CANopen bus;

Use the free protocol to control the exposure of the optical machine through the RS-232 interface;

Read the readings of the optical power meter through the RS-485 bus Modbus protocol;

Connect the limit switch and grating through the built-in I/O interface, eliminating the need to install additional I/O slave stations;

Such a high-precision 3D printer has been upgraded!