CN114083795A

CN114083795A - Reducing dredging electric jet printing device

Info

Publication number: CN114083795A
Application number: CN202110769993.9A
Authority: CN
Inventors: 李凯; 韩小帅; 刘麦祺; 王晓英
Original assignee: Ningbo University
Current assignee: Ningbo University
Priority date: 2021-07-04
Filing date: 2021-07-04
Publication date: 2022-02-25

Abstract

The invention belongs to the technical field of advanced manufacturing, and relates to a reducing dredging electric jet printing device which comprises an electric jet printing module, a reducing dredging module and a motion control module. Firstly, transporting functional ink to a nozzle at a fixed flow rate by using fluid pressure, then applying high voltage between a printing substrate and a nozzle, and forming fine jet flow by the functional ink at the nozzle under the composite action of electric field force, gravity and surface tension; after the spray head is blocked, the clamping platform drives the spray head to rotate 90 degrees to reach a preset position through the spray head clamp, and the pressing strip and the fastening piece on the spray needle are driven by utilizing piezoelectric ceramics (also called PZT) to realize the adjustment of the inner diameter of the spray needle and finally dredge the blocked spray needle. The reducing dredging electric jet printing device has the advantages of low cost, wide applicability and the like.

Description

Reducing dredging electric jet printing device

Technical Field

The invention belongs to the technical field of advanced manufacturing, and relates to a reducing dredging electric jet printing device.

Background

The printing technology, also known as additive manufacturing technology, is a novel technology for constructing an object by a layer-by-layer printing mode on the basis of a digital model, and has the advantages of rapid forming, no need of a template and the like. The spray head in the printing equipment is a key component, not only influences the printing structural characteristics, but also relates to the stability of the printing process. The spray head is inevitably blocked in the working process. If functional particles in the ink agglomerate or settle, large-diameter particles can be induced, and under the thrust of the injection pump, the large-diameter particles can be pushed into the spray needle to cause the spray head to be blocked, so that the printing equipment cannot work normally. The traditional nozzle dredging mode comprises the modes of mechanical vibration, nozzle cleaning and the like, the mechanical vibration mode can directly put the nozzle into a vibration environment, and the resonance effect is utilized to crush large-diameter particles; the nozzle cleaning mode needs to disassemble the nozzle from the printing equipment and dredge the nozzle in a heating or mechanical conduction mode. Although the mechanical vibration mode is simple, when the nozzle is placed in a vibration environment, the stability of the functional ink is influenced while the small particles are crushed; the shower nozzle clearance need be dismantled the shower nozzle from printing apparatus, and not only technology is loaded down with trivial details, difficult operation moreover, and when orifice internal diameter is less very much, the mediation is more difficult.

Disclosure of Invention

The invention aims to overcome the technical defects and invents a variable diameter dredging electric jet printing device. Firstly, transporting functional ink to a nozzle at a fixed flow rate by using fluid pressure, then applying high voltage between a printing substrate and a nozzle, and forming fine jet flow by the functional ink at the nozzle under the composite action of electric field force, gravity and surface tension; after the spray head is blocked, the clamping platform drives the spray head to rotate 90 degrees to reach a preset position through the spray head clamp, and the pressing strip and the fastening piece on the spray needle are driven by utilizing piezoelectric ceramics (also called PZT) to realize the adjustment of the inner diameter of the spray needle and finally dredge the blocked spray needle. The reducing dredging electric jet printing device has the advantages of low cost, wide applicability and the like.

The technical scheme adopted by the invention is as follows:

a reducing dredging electric jet printing device comprises an electric jet printing module, a reducing dredging module and a motion control module. The device firstly applies pressure to a syringe by using a syringe pump, functional ink in the syringe is extruded into an ink reservoir, and simultaneously, under the action of the pushing force of the syringe, the functional ink in the ink reservoir flows to a nozzle at a certain fixed flow rate, a high-voltage electric field is applied between a printing substrate and a nozzle, and the functional ink at the nozzle forms fine jet under the action of electric field force and gravity. In the printing process, after the spray head is blocked, the clamping platform drives the spray head to rotate by 90 degrees through the spray head clamp to reach a preset position, appropriate voltage is applied to the two piezoelectric ceramics by utilizing the inverse piezoelectric effect of the piezoelectric ceramics, the displacement output by the piezoelectric ceramics is directly applied to the pressing strip, the inner diameter of the fastener is enlarged due to the enlargement of the caliber of the pressing strip, the spray needle is formed by drawing an elastic material, the inner diameter of the spray needle is enlarged under the action of elasticity, so that large-diameter particles in the spray needle smoothly flow out, after the spray needle is dredged, voltage in the opposite direction is applied to the piezoelectric ceramics, and the inner diameter of the spray needle is reduced through the pressing strip and the fastener; the clamping platform drives the spray head to rotate 90 degrees in the reverse direction through the spray head clamp, and the initial position is recovered to continue printing.

The electronic injection printing module comprises an injection pump, an injector, functional ink, a sealing guide pipe, a nozzle, an ink reservoir, a connecting pipe, a spray needle, a nozzle clamp and a voltage controller; the injection pump is powered by an alternating current power supply, the injector is clamped and fixed on the injection pump, the injection pump is electrified to extrude functional ink in the injector, and one end of a needle head of the injector is connected with the upper end of the spray head through a sealing guide pipe; the nozzle is composed of an ink reservoir, a connecting pipe and a spray needle, the nozzle is positioned and clamped through a nozzle clamp, the ink reservoir is made of special materials and used for storing functional ink, the connecting pipe is made of elastic materials, the upper end of the connecting pipe is connected with the ink reservoir in an interference mode, the lower end of the connecting pipe is connected with the spray needle, stable circulation of the functional ink is achieved, the spray needle is formed by drawing spring steel, the tip of the spray needle is conical, and the spray needle has the advantages of being low in friction coefficient, adjustable in aperture and the like; the voltage controller provides an alternating current power supply, the voltage output range is adjustable, and the output end of the voltage controller is connected with the conductive part of the spray head clamp.

The reducing dredging module comprises a clamping platform, a fastener-I, a fastener-II, a layering-I, a layering-II, piezoelectric ceramic-I, piezoelectric ceramic-II and a waste trough; the clamping platform positions and clamps the spray head through the spray head clamp, and can drive the spray head to rotate and also can drive the spray head to move up and down so as to adjust the distance between the spray head and the printing substrate; the fastening pieces-I and-II are made of elastic materials, have adjustable inner diameters and are respectively sleeved at the upper end and the lower end of the spray needle; the pressing strips-I and-II are made of plastic materials, can not deform after being subjected to tensile force and are respectively bound on the outer surfaces of the fastening piece-I and the fastening piece-II, and the tail ends of the pressing strips-I and the pressing strips-II are respectively connected with the output ends of the piezoelectric ceramics-I and the piezoelectric ceramics-II; the piezoelectric ceramics-I and piezoelectric ceramics-II have inverse piezoelectric effect, and apply voltage to the positive electrode and the negative electrode of the piezoelectric ceramics-I and piezoelectric ceramics-II to enable the piezoelectric ceramics-I and piezoelectric ceramics-II to generate displacement in the direction vertical to the potential difference, the output displacement is transmitted to a fastening piece through the pressing strips-I and-II, and the inner diameter of the spray needle is adjusted by the caliber change of the fastening piece; the voltage controller provides alternating current, the voltage output range is adjustable, and the output voltage of the voltage controller is adjusted to adjust the displacement output by the piezoelectric ceramic; the waste material groove is arranged below the spray head which rotates for 90 degrees and is used for containing the blocked functional ink.

The motion control module comprises a printing substrate, a motion platform, a computer controller and a high-definition CCD camera. The printing substrate is used for bearing a structure sprayed by a spray needle, and the lower end of the printing substrate is fixed on the motion platform by an insulating screw and a gasket so as to be capable of moving along with the motion platform in the same way; the motion platform is powered by an alternating current power supply and can realize motion in X-Y directions; the high-definition CCD camera is aligned with the printing area, the high-definition CCD camera is used for measuring the space appearance of the printing substrate, the observed data of the printing substrate is transmitted to the computer controller through the USB data line, the computer controller controls the movement speed and the track of the movement platform in the X-Y plane through a program, and meanwhile, the distance between the spray needle and the printing substrate can also be adjusted in real time through the clamping platform.

The device is adopted to carry out reducing dredging electro-jet printing, and the method comprises the following steps:

first, the formation of a jet under the composition of multiple physical fields

The printing substrate is placed on the motion platform and clamped and fixed, the space morphology of the printing substrate is identified through the high-definition CCD camera, the measured information is transmitted to the computer controller through the USB data line, and the computer controller adjusts the distance between the spray head and the printing substrate in real time. Functional ink is injected into a nozzle through an injection pump, the nozzle is clamped and fixed on a nozzle clamp, the nozzle clamp is clamped through a clamping platform, the nozzle can move along with the nozzle clamp in the vertical direction to realize the adjustment of the height of jet printing, the flow rate of the functional ink is adjusted by controlling the pressure applied to an injector by the injection pump, in order to obtain fine jet flow, an electric field is introduced between the nozzle clamp and a printing substrate, a voltage controller is opened, a high voltage power supply applies high voltage to the nozzle through a conductive nozzle clamp, at the moment, strong electric field force is formed between the nozzle and the printing substrate, the functional ink in the nozzle is subjected to the actions of electric field force, gravity, solution surface tension/dielectric force/viscous force and the like, the parameters are mutually coordinated, stable jet flow far smaller than the inner diameter of a nozzle needle is finally formed, and the computer controller automatically controls the movement of the movement platform in the X-Y direction according to preset printed patterns, thereby achieving accurate printing.

Secondly, adjusting the inner diameter of the spray needle to dredge the spray head

Along with the printing, the sedimentation phenomenon can appear in the function ink, and under the effect of syringe pump thrust, the granule of major diameter can be pushed into the needle in, arouses the needle jam, influences equipment normal operating. The high-definition CCD camera monitors the printing process in real time in the printing process, when a spray needle is blocked, the high-definition CCD camera transmits the measured information to the computer controller through a USB data line, the computer controller controls the injection pump to stop applying pressure to the injector through a program, meanwhile, the clamping platform drives the spray head to rotate 90 degrees to reach a preset position through the spray head clamp, proper voltage is applied to the piezoelectric ceramic-I and the piezoelectric ceramic-II by utilizing the inverse piezoelectric effect of the piezoelectric ceramic-I and the piezoelectric ceramic-II, the displacement output by the piezoelectric ceramic-I and the piezoelectric ceramic-II is directly applied to the pressing strips-I and the pressing strips-II, the inner diameters of the fastening pieces-I and the fastening pieces-II are increased due to the increase of the calibers of the pressing strips-I and the pressing strips-II, so that the constraint on the spray needle is reduced, the spray needle is formed by drawing of an elastic material, and the inner diameter of the spray needle is increased under the action of elastic force, therefore, large-diameter particles in the spray needle smoothly flow into a waste material groove below the spray needle, different voltages are applied to the piezoelectric ceramic-I and the piezoelectric ceramic-II, and the cross-scale adjustment of the inner diameter of the spray needle can be realized. After the spray needle is dredged, voltages in opposite directions are applied to the piezoelectric ceramics-I and the piezoelectric ceramics-II, the inner diameter of the spray needle is reduced through the pressing strip-I, the pressing strip-II, the fastening piece-I and the fastening piece-II, the clamping platform drives the spray head to rotate in the opposite direction by 90 degrees through the spray head clamp, and the spray head is recovered to the initial position to continue printing.

The invention has the beneficial effects that: a reducing dredging electric jet printing device realizes quick dredging of the reducing of a printing nozzle. The high-definition CCD camera is used for measuring the spatial appearance of the printing substrate, and the computer controller can adjust the position of the spray head in the vertical direction in real time according to the appearance characteristics of the printing substrate; the functional ink forms fine jet under the comprehensive action of electric field force, gravity, solution surface tension/dielectric force/viscous force and the like; after the spray head is blocked in the printing process, the clamping platform drives the spray head to rotate for 90 degrees through the spray head clamp to reach a preset position, the output of different displacements is realized by applying proper voltage to the two piezoelectric ceramics by utilizing the inverse piezoelectric effect of the piezoelectric ceramics, the output displacement is transmitted through the pressing strip and the fastener, and finally the adjustment of the inner diameter of the spray needle is realized, so that the blocked spray needle is dredged. The electric jet printing device has the advantages of low cost, wide applicability and the like.

Drawings

FIG. 1 is a schematic diagram of a diameter-variable dredging electric jet printing device in an embodiment of the invention.

Fig. 2 is a schematic view of an apparatus for rotating a spray head by 90 ° in the embodiment of the present invention.

FIG. 3 is a schematic diagram of a device for realizing needle reducing and dredging in the embodiment of the invention.

In the figure: the device comprises a syringe pump 1, a syringe 2, functional ink 3, a sealing guide pipe 4, a spray head 5, an ink reservoir 501, a connecting pipe 502, a spray needle 503, a spray head clamp 6, a clamping platform 7, a fastener I8, a fastener II9, a layering I10, a layering II11, a piezoelectric ceramic I13, a piezoelectric ceramic II 14, a printing substrate 14, a motion platform 15, a computer controller 16, a high-definition CCD camera 17, a voltage controller 18 and a waste material groove 19.

Detailed Description

The following detailed description of the embodiments of the invention refers to the accompanying drawings. See fig. 1-3.

The embodiment discloses a reducing dredging electric jet printing device which mainly comprises an electric jet printing module, a reducing dredging module and a motion control module. Firstly, measuring the spatial appearance of a printing substrate by using a high-definition CCD camera, and adjusting the position of a spray head in the vertical direction by a computer controller according to the appearance characteristic of the printing substrate; the functional ink obtains fine jet under the comprehensive actions of electric field force, gravity, solution surface tension/dielectric force/viscous force and the like; after the spray head is blocked in the printing process, the clamping platform drives the spray head to rotate for 90 degrees through the spray head clamp to reach a preset position, appropriate voltage is applied to the two piezoelectric ceramics by utilizing the inverse piezoelectric effect of the piezoelectric ceramics to realize output of different displacements, the output displacements are transmitted through the pressing strips and the fasteners, and finally the adjustment of the inner diameter of the spray needle is realized, so that blocked particles in the spray needle smoothly flow out.

The electronic injection printing module comprises an injection pump 1, an injector 2, functional ink 3, a sealing conduit 4, a nozzle 5, an ink reservoir 501, a connecting pipe 502, a nozzle 503, a nozzle clamp 6 and a voltage controller 18; the injection pump 1 is powered by a 220V alternating current power supply, the injector 2 is clamped and fixed on the injection pump 1, the injection pump 1 is electrified to extrude the functional ink 3 in the injector 2, and one end of a needle head of the injector 2 is connected with the upper end of the spray head 5 through a sealing conduit 4; the sprayer 5 consists of an ink reservoir 501, a connecting pipe 502 and a spray needle 503, the sprayer 5 is positioned and clamped through a sprayer clamp 6, the ink reservoir 501 is made of special materials and used for storing functional ink 3, the connecting pipe 502 is made of elastic materials, the upper end of the connecting pipe 502 is connected with the ink reservoir 501 in an interference mode, the lower end of the connecting pipe 502 is connected with the spray needle 503 to realize stable circulation of the functional ink 3, the spray needle 503 is formed by drawing spring steel, the tip of the spray needle is conical, and the sprayer has the advantages of low friction coefficient, adjustable aperture and the like; the voltage controller 18 provides an alternating current power supply, the voltage output range is adjustable, and the output end of the voltage controller is connected with the conductive part of the spray head clamp 6.

The reducing dredging module comprises a clamping platform 7, a fastener-I8, a fastener-II 9, a pressing bar-I10, a pressing bar-II 11, piezoelectric ceramic-I12, piezoelectric ceramic-II 13 and a waste trough 19; the clamping platform 7 positions and clamps the spray head 5 through the spray head clamp 6, and the clamping platform 7 can drive the spray head 5 to rotate and can also drive the spray head 5 to move up and down so as to adjust the distance between the spray head 5 and the printing substrate 16; the fastener-I8 and the fastener-II 9 are made of elastic materials, have adjustable inner diameters and are respectively sleeved at the upper end and the lower end of the spray needle 503; the pressing strips-I10 and-II 11 are made of plastic materials, cannot deform after being pulled, and are respectively bound on the outer surfaces of the fastening pieces-I8 and fastening pieces-II 9, and the tail ends of the pressing strips-I10 and-II 11 are respectively connected with the output ends of the piezoelectric ceramics-I12 and the piezoelectric ceramics-II 13; the piezoelectric ceramics-I12 and the piezoelectric ceramics-II 13 have inverse piezoelectric effect, voltages are applied to the positive electrode and the negative electrode of the piezoelectric ceramics-I12 and the piezoelectric ceramics-II 13, so that the piezoelectric ceramics-I12 and the piezoelectric ceramics-II 13 can generate displacement in the direction vertical to the potential difference, the output displacement is transmitted to the fastening piece-I8 and the fastening piece-II 9 through the pressing strip-I10 and the pressing strip-II 11, and the inner diameter of the spray needle 503 is adjusted by the caliber change of the fastening piece; the voltage controller 18 provides alternating current, the voltage output range is adjustable, and the output displacement of the piezoelectric ceramics-I12 and piezoelectric ceramics-II 13 is adjusted by adjusting the output voltage of the voltage controller 18; the waste tank 19 is arranged below the spray head 5 which rotates for 90 degrees and is used for containing the blocked functional ink 3.

The motion control module comprises a printing substrate 14, a motion platform 15, a computer controller 16 and a high-definition CCD camera 17; the printing substrate 14 is used for bearing a structure sprayed by the spray needle 503, and the lower end of the printing substrate 14 is fixed on the moving platform 15 by using an insulating screw and a gasket, so that the printing substrate can move along with the moving platform 15; the motion platform 15 is powered by a 220V alternating current power supply and can realize motion in two directions of X-Y; the high-definition CCD camera 17 is aligned with the printing area, the high-definition CCD camera 17 is used for measuring the space appearance of the printing substrate 14, the observed data is transmitted to the computer controller 16 through the USB data line, and the computer controller 16 controls the movement speed and the track of the movement platform 15 through a program.

In order to achieve the purpose, the invention adopts the technical scheme that:

the device is used for reducing dredging electro-jet printing, and the specific implementation steps are as follows:

first, the formation of a jet under the composition of multiple physical fields

Placing a printing substrate 14 with a thickness of 0.5-200 μm on the moving platform 16 and clamping and fixing it; detecting the appearance of the printing substrate 14 by using a high-definition CCD camera 17, wherein the refresh rate of the high-definition CCD camera 17 is 75Hz-120Hz, transmitting the measured information to a computer controller 16 by using a USB data line, and adjusting the distance between the spray head 5 and the printing substrate 14 in real time by the computer controller 16; a syringe 2 with the range of 5-150 mu L is fixed above the injection pump 1, the syringe 2 is connected with the upper end of a nozzle 5 through a sealing conduit 4, the functional ink 3 is injected into the ink reservoir 501 by applying pressure to the syringe 2, the injection pump 1 applies 10-2000N pressure to the syringe 2, and the flow rate of the functional ink 3 is adjusted to be 0.1-1000 mu L/min; the spray head 5 is clamped and fixed on the spray head clamp 6, the spray head clamp 6 is clamped through the clamping platform 7, and the spray head 5 can move in the vertical direction along with the spray head clamp 6 to realize the adjustment of the spray printing height; in order to obtain fine jet flow, an electric field is introduced between the nozzle clamp 6 and the printing substrate 14, a voltage controller 18 is opened, the voltage regulation range of the voltage controller 18 is 100-2800V, and a proper high voltage is applied to the nozzle 5 through the conductive nozzle clamp 6, so that strong electric field force is formed between the nozzle 5 and the printing substrate 14; the functional ink 3 in the nozzle 5 is subjected to the comprehensive action of electric field force, gravity, solution surface tension/dielectric force/viscous force, and the parameters are coordinated with each other, so that stable jet flow with the diameter of 0.5-50 mu m is finally formed at the nozzle 503.

Along with the printing, the functional ink 3 is deposited, and under the thrust of the injection pump 1, particles with larger diameters can be pushed into the spray needle 503 to cause the spray needle 503 to be blocked, so that the normal operation of the equipment is influenced; the high-definition CCD camera 17 monitors the printing process in real time in the printing process, when the spray needle 503 is blocked, the high-definition CCD camera 17 transmits information to the computer controller 16, the computer controller 16 controls the injection pump 1 to stop applying pressure to the injector 2 through a PLC program, meanwhile, the clamping platform 7 drives the spray head 5 to rotate 90 degrees to reach a preset position through the spray head clamp 6, and the rotating speed is 0.1-10 rad/s; the piezoelectric coefficients of the piezoelectric ceramics-I12 and piezoelectric ceramics-II 13 are 7.9 mu m/100V, the inverse piezoelectric effect of the piezoelectric ceramics is utilized, 0-150V voltage is applied to the piezoelectric ceramics-I12, 0-150V voltage is applied to the piezoelectric ceramics-II 13, the piezoelectric ceramics-I12 outputs 0-11.5 mu m displacement, and the piezoelectric ceramics-II 13 outputs 0-11.5 mu m displacement; the generated displacement output enables the inner diameter variation range of the batten-I10 to be 0.3-0.6 mu m, and the inner diameter variation range of the batten-II 11 to be 0.18-0.5 mu m; variations in the inner diameters of bead-I10 and bead-II 11 caused variations in the inner diameters of fastener-I8 and fastener-II 9, with fastener-I8 having an inner diameter ranging from 0.3 μm to 0.6 μm and fastener-II 9 having an inner diameter ranging from 0.18 μm to 0.5 μm; the spray needle 503 is formed by drawing an elastic material, and the inner diameter of the spray needle 503 is changed within the range of 0.18-0.5 μm under the action of elasticity, so that large-diameter particles in the spray needle 503 can smoothly flow into the waste tank 19 below; after the spray needle 503 is dredged, voltages in opposite directions are applied to the piezoelectric ceramic-I12 and the piezoelectric ceramic-II 13, the inner diameter of the spray needle 503 is reduced through the pressing strip-I10, the pressing strip-II 11 and the fastening piece-I8 and the fastening piece-II 9, the clamping platform 7 drives the spray head 5 to rotate in the opposite direction by 90 degrees through the spray head clamp 6, and the spray head 5 is recovered to the initial position to continue printing.

Claims

1. A reducing dredging electric jet printing device is characterized in that the printing device comprises an electric jet printing module, a reducing dredging module and a motion control module; the electronic injection printing module comprises an injection pump (1), an injector (2), functional ink (3), a sealing guide pipe (4), a nozzle (5), an ink storage device (501), a connecting pipe (502), a spray needle (503), a nozzle clamp (6) and a voltage controller (18); the injection pump (1) is powered by an alternating current power supply, the injector (2) is clamped and fixed on the injection pump (1), the injection pump (1) is electrified to extrude functional ink (3) in the injector (2), and one end of a needle head of the injector (2) is connected with the upper end of the spray head (5) through a sealing conduit (4); the sprayer (5) consists of an ink reservoir (501), a connecting pipe (502) and a spray needle (503), the sprayer (5) is positioned and clamped through a sprayer clamp (6), the ink reservoir (501) is used for storing functional ink (3), the upper end of the connecting pipe (502) is connected with the ink reservoir (501) in an interference mode, the lower end of the connecting pipe is connected with the spray needle (503) to realize stable circulation of the functional ink (3), and the tip of the spray needle (503) is conical; the voltage controller (18) provides an alternating current power supply, the voltage output range is adjustable, and the output end of the voltage controller is connected with the conductive part of the spray head clamp (6);

the reducing dredging module comprises a clamping platform (7), a fastener-I (8), a fastener-II (9), a pressing bar-I (10), a pressing bar-II (11), piezoelectric ceramics-I (12), piezoelectric ceramics-II (13) and a waste material tank (19); the spray head (5) is positioned and clamped by the clamping platform (7) through the spray head clamp (6), and the clamping platform (7) can drive the spray head (5) to rotate and can also drive the spray head (5) to move up and down; the inner diameters of the fastener-I (8) and the fastener-II (9) are adjustable, and the fasteners are respectively sleeved at the upper end and the lower end of the spray needle (503); the pressing strips-I (10) and-II (11) are not deformable after being subjected to tension and are respectively bound on the outer surfaces of the fastening pieces-I (8) and fastening pieces-II (9), and the tail ends of the pressing strips-I (10) and-II (11) are respectively connected with the output ends of the piezoelectric ceramics-I (12) and the piezoelectric ceramics-II (13); the displacement output by the piezoelectric ceramics-I (12) and piezoelectric ceramics-II (13) is transmitted to the fastening piece-I (8) and the fastening piece-II (9) through the pressing strip-I (10) and the pressing strip-II (11), and the inner diameter of the spray needle (503) is adjusted by the caliber change of the fastening piece; the voltage controller (18) provides alternating current, the voltage output range is adjustable, and the output displacement of the piezoelectric ceramics-I (12) and piezoelectric ceramics-II (13) is adjusted by adjusting the output voltage of the voltage controller (18); the waste material groove (19) is arranged below the spray head (5) which rotates for 90 degrees and is used for containing the blocked functional ink (3);

the motion control module comprises a printing substrate (14), a motion platform (15), a computer controller (16) and a high-definition CCD camera (17); the printing substrate (14) is used for bearing a structure sprayed by the spray needle (503), and the lower end of the printing substrate (14) is fixed on the moving platform (15) by an insulating screw and a gasket so as to enable the printing substrate to move along with the moving platform (15) in the same way; the motion platform (15) is powered by an alternating current power supply and can realize motion in X-Y directions; the high-definition CCD camera (17) is aligned to the printing area, the high-definition CCD camera (17) is used for measuring the space morphology of the printing substrate (14), the observed data is transmitted to the computer controller (16) through the USB data line, and the computer controller (16) controls the movement speed and the track of the movement platform (15) through a program.

2. The printing apparatus of claim 1 for variable diameter deoccluding electrojet printing, comprising the steps of:

first, the formation of a jet under the composition of multiple physical fields

Placing a printing substrate (14) on a motion platform (15) and clamping and fixing the printing substrate, identifying the spatial morphology of the printing substrate (14) through a high-definition CCD (charge coupled device) camera (17), transmitting the measured information to a computer controller (16) through a USB (universal serial bus) data line, and adjusting the distance between a spray head (5) and the printing substrate (14) in real time through the computer controller (16); functional ink (3) is injected into a nozzle (5) through an injection pump (1), the nozzle (5) is clamped and fixed on a nozzle clamp (6), the nozzle clamp (6) is clamped through a clamping platform (7), the nozzle (5) can move along with the nozzle clamp (6) in the vertical direction to realize the adjustment of the jet printing height, the flow rate of the functional ink (3) is adjusted by controlling the pressure applied to an injector (2) by the injection pump (1), an electric field is introduced between the nozzle clamp (6) and a printing substrate (14) in order to obtain fine jet flow, a voltage controller (18) is opened, a high voltage is applied to the nozzle (5) through a conductive nozzle clamp (6) by a high voltage source, a strong electric field force is formed between the nozzle (5) and the printing substrate (12), and the functional ink (3) in the nozzle (5) is acted by the electric field force, gravity, solution surface tension/dielectric force/viscous force, the parameters are coordinated with each other to finally form stable jet flow which is far smaller than the inner diameter of the spray needle (503), and the computer controller (16) automatically controls the movement of the motion platform (15) in the X-Y direction according to the preset printed pattern, thereby realizing accurate printing;

Along with the printing, the functional ink (3) can generate a deposition phenomenon, and under the action of the thrust of the injection pump (1), particles with larger diameters can be pushed into the spray needle (503), so that the spray needle (503) is blocked, and the normal operation of equipment is influenced; the high-definition CCD camera (17) monitors the printing process in real time in the printing process, when a spray needle (503) is blocked, the high-definition CCD camera (17) transmits the measured information to a computer controller (16) through a USB data line, the computer controller (16) controls an injection pump (1) to stop applying pressure to an injector (2) through a program, meanwhile, a clamping platform (7) drives a spray head (5) to rotate 90 degrees to reach a preset position through a spray head clamp (6), proper voltage is applied to the clamping platform by utilizing the inverse piezoelectric effect of piezoelectric ceramics-I (12) and piezoelectric ceramics-II (13), the displacement output by the piezoelectric ceramics-I (12) and the piezoelectric ceramics-II (13) is directly applied to a pressure strip-I (10) and a pressure strip-II (11), the bore diameters of the pressure strip-I (10) and the pressure strip-II (11) are increased to cause the bore diameters of a fastener-I (8) and a fastener-II (9) to be increased, therefore, the restriction on the spray needle (503) is reduced, the spray needle (503) is formed by drawing an elastic material, and the inner diameter of the spray needle (503) is enlarged under the action of elastic force, so that large-diameter particles in the spray needle (503) smoothly flow into a waste material tank (19) below, and voltages with different sizes are applied to the piezoelectric ceramic-I (12) and the piezoelectric ceramic-II (13), so that the inner diameter of the spray needle (503) can be adjusted in a cross-scale mode; after the spray needle (503) is dredged, voltages in opposite directions are applied to the piezoelectric ceramic-I (12) and the piezoelectric ceramic-II (13), the inner diameter of the spray needle (503) is reduced through the pressing strip-I (10), the pressing strip-II (11), the fastening piece-I (8) and the fastening piece-II (9), the clamping platform (7) drives the spray head (5) to rotate in the opposite direction by 90 degrees through the spray head clamp (6), and the spray head is recovered to the initial position to continue printing.