Research On Key Technologies Of 3D Inkjet Printing Device Based On 2D Printing Technology

Ink-jet 3D printing technology is one of the rapidly developing 3D printing technologies in recent years.Ink-jet 3D printing has some problems,such as high cost and inability of slice control software to be used in 2D printer based printing device.In order to solve the above problems,this paper develops a set of inkjet3 D printing device based on two-dimensional inkjet printer,and independently designs the mechanical structure,control system and slicing software of the device.The main research contents include:Firstly,the working principle of inkjet 3D printing technology is analyzed,and the overall design scheme of the inkjet 3D printing device is determined,including mechanical structure design scheme,control system design scheme,and slicing software design scheme.The cost,size,structure,nozzle stability,printing method,and other requirements of the inkjet 3D printing device are analyzed to determine the technical indicators that the inkjet 3D printing device must be satisfied,including the device size of 600×600×600 mm,the maximum forming size of 200×200×200 mm,single color printing,monochromatic piezoelectric on-demand jet,automatic printing,which can operate normally in the Windows operating system,etc.Secondly,the workflow of the two-dimensional inkjet printer is studied,and the two-dimensional inkjet printer is used as the injection device of the inkjet 3D printing device,and its mechanical structure is modified.The mechanical structure of each part of the device is designed in detail,including the injection device,the powder-laying device,the forming table,and the powder-feeding table.The synchronous belt slider is selected as the longitudinal motion transmission mode of the injection device and the powder laying device in the Y axis,and the screw nut is used as the vertical motion transmission mode of the forming table and the powder feeding table in the Z axis.Third,according to the functional requirements of the control system,the overall structure of the control system is designed,including the main controller,motion control module,signal detection module,paper control module,serial communication module,and power module.STM32F103 ZET is selected as the main controller,57 stepper motor,DM542 stepper motor drive and limit switch are selected as the main components of the motion control module,the incremental encoder is selected as the important components of signal detection and feed control module,and the wiring between the components is designed.Design a serial communication protocol between inkjet 3D printing control system and slicing software;the control flow of each module of the control system is designed and developed to realize the three-dimensional motion control of the system,signal detection,and line change control of the injection device,and serial communication control.Fourthly,according to the function of slicing software,including STL model’s reading,model visualization,slicing,contour filling,printing,and communication,QT and OSG are chosen to develop the function of slicing software.The equal thickness slicing algorithm and the parallel scan line algorithm are described in detail,and they are used to realize the layered slicing and contour filling functions.Select the vector format as a contour line after filling the saved picture,speed up the slicing speed and reduce the model’s twodimensional image printing distortion.Fifth,the slicing software was tested independently,and the model slicing and filling effect was good.The generation speed of two-dimensional vector map of model contour was faster than that of bitmap,the generating accuracy of vector map was higher than that of bitmap,and the generating time of vector map was shorter than that of bitmap,which could meet the requirements of inkjet 3D printing device.Sixth,the inkjet 3D printing device,control system and slicing software were integrated for printing test.Different plaster powders were tested,and the material with the best effect was selected for subsequent experiments.Confirmed through the experiment of powder particle size range in 1 ～ 9 μm powder effect is best,nozzle and powder molding machine shop are the plane of the optimum distance is 1.5 mm,best pave powder thickness of 0.2 mm;six kinds of spray solution with different concentration ratio of ink and binder were configured for printing.The compressive strength and porosity test showed that with the increase of binder,the stress value and porosity increased first and then decreased.When the concentration ratio of ink and binder was 10:8,the maximum stress value was 225 KPa and the minimum porosity was 6.02%.