CN105366625B - A kind of electromagnetic force shower nozzle based on MEMS technology - Google Patents

Abstract

The invention relates to an electromagnetic spray head based on MEMS technology, which includes a conductive coil, a soft magnetic material, a silicon material, a control chip, a conductive fluid, and an electrode pair; the conductive coil is placed inside the soft magnetic material, and the silicon material includes The positive and negative poles of the conductive coil are respectively connected to the positive and negative poles of the electrode pair. The control chip is placed on the top of the silicon material. Flow out from the bottom of the hole, and the electrode pair runs through the soft magnetic material and silicon material to connect with the control chip on the top, so as to realize the micro-flow control of the conductive fluid. Based on the MEMS process, the miniature electromagnetic force nozzle is manufactured. After power on, the conductive coil in series generates a magnetic field, and the electrode pair generates an electric field. The electromagnetic force formed by the electromagnetic field drives the conductive fluid in the nozzle to flow vertically downward. It has the advantages of simple structure, high precision and high frequency. High performance, low noise, low heat and high reliability.

Description

An Electromagnetic Force Nozzle Based on MEMS Technology

technical field

The invention relates to an electromagnetic spray head based on MEMS technology, which has no noise, no heat, no vibration and no driving mechanism, and is applied in the field of micro-flow control of conductive fluid with high precision, high frequency and high reliability.

Background technique

The MEMS manufacturing process is a general term for microstructure processing processes down to the nanometer scale and up to the millimeter scale. Mainly include: integrated circuit process technology (processing silicon materials with thin film deposition, patterning and etching technologies to form silicon-based MEMS devices), LIGA technology (photolithography, electroforming and plastic casting to form deep microstructures to manufacture MEMS device). The main feature of silicon MEMS processing technology is that the deep etching of silicon substrate materials can obtain movable microstructures with large longitudinal dimensions. Silicon processes include wet SOG (silicon on glass) process, dry SOG process, front silicon process, SOI (Silicon On Insulator) process. The surface MEMS processing technology mainly completes the manufacture of MEMS devices by growing multi-layer films such as silicon oxide, silicon nitride, and polysilicon on silicon wafers. The vertical size of the movable microstructure obtained by using the surface technology is small.

Inkjet printers can be divided into thermal bubble type and piezoelectric type according to the working principle.

Thermal bubble inkjet technology means that the nozzle is filled with ink. When the heater is applied with voltage, the heating unit starts in a short time, so that the ink around the heating unit is heated in a short time to form micro-bubbles, and the ink vaporizes at an extremely fast speed. When it melts, the small bubbles will become bigger, and the bubbles will expand to the maximum, and the ink will be squeezed out by the expansion force. Then the air bubbles in the nozzle shrink rapidly, so that the extruded ink forms ink droplets, so that the ink droplets extruded from the nozzle will be sprayed on the paper. After the ink is squeezed out, the bubbles disappear and a capillary phenomenon occurs, so that the nozzle is filled with ink again, thus completing an inkjet cycle.

Piezoelectric inkjet technology uses the shape change caused by the inherent inverse piezoelectric effect of piezoelectric ceramic materials to act on the ink chamber to form ink droplets. Piezoelectric ceramic materials will produce shape changes under the action of an external electric field, such as elongation ( shortening and shear deformation). When the applied electric field is perpendicular to the polarization direction of the piezoelectric ceramic material, the material undergoes shear deformation, forming inkjet pressure, and the inkjet tube extrudes ink under pressure to form ink droplets, which are ejected at high speed and sprayed onto the substrate image on top.

Thermal bubble print head is prone to chemical changes at high temperature and unstable in nature, so the color authenticity will be affected to a certain extent; ink is ejected through air bubbles, and the directionality and size of ink particles are not easy to grasp , the edge of the printing line is easy to be uneven, which affects the printing quality to a certain extent. The micro piezoelectric print head is damaged or blocked, and the whole printer needs to be repaired; under high-frequency jetting, piezoelectric jetting will make a lot of noise.

In view of the above deficiencies, the present invention is based on the Lorentz force theory of electromagnetic field, that is, the orthogonal (vertical) distributed electric field and magnetic field can generate Lorentz force to the conductor placed therein, making it along the simultaneous orthogonal (vertical) Movement in both electromagnetic and magnetic directions. Using the Lorentz force, that is, the electromagnetic force, the conductive fluid (such as: conductive ink) can be driven to move at room temperature, and the size of the electromagnetic force can be adjusted by controlling the chip to achieve high precision, high frequency, high efficiency, no heat, no noise, Vibration-free microfluidic jetting.

Contents of the invention

The object of the present invention is to provide an electromagnetic nozzle based on MEMS technology, which has the characteristics of simple structure, high precision, high frequency, high efficiency, no heat, no noise, no vibration, and no driving mechanism. The electromagnetic field inside the nozzle acts on the conductive fluid to generate electromagnetic force, which drives the directional flow of the conductive fluid, and the control chip adjusts the strength of the electromagnetic field and starts and stops to control the flow rate and frequency of the fluid.

To achieve the above object, design of the present invention is as follows:

An electromagnetic nozzle based on the MEMS technology of the present invention has a conductive coil, including: 2 positive terminal terminals and 2 negative terminal terminals; a number of conductive coils are connected in series at the left and right ends of the nozzle hole, and the electromagnetic poles in the same direction are formed after conduction. The positive pole of the conductive coil formed by the left end connected in series is connected with the positive pole of the electrode pair, the negative pole of the conductive coil formed by the left end connected in series is connected with the negative pole of the electrode pair; the positive pole of the conductive coil formed by the right end connected in series is connected with the positive pole of the electrode pair, and the right end is connected in series The negative pole of the conductive coil is connected to the negative pole of the electrode pair.

An electromagnetic nozzle based on the MEMS technology of the present invention has a soft magnetic material and is coated with a conductive coil. The electromagnetic field formed after electrification is confined inside the soft magnetic material and will not leak to the outside of the soft magnetic material; The nozzle hole flows conductive fluid, and there are electromagnetic poles composed of conductive coils on the left and right of the nozzle hole, and an electric field composed of electrode pairs before and after the nozzle hole.

An electromagnetic spray head based on the MEMS technology of the present invention has silicon material as the basic carrier of the electromagnetic force spray head, coated with soft magnetic material, has electrode pairs inside, a control chip on the top, and a nozzle hole on the bottom to flow conductive fluid.

An electromagnetic force nozzle based on the MEMS technology of the present invention has a control chip, a nozzle hole in the middle to flow conductive fluid, a silicon material at the bottom, an external power supply at the top, and a built-in circuit to control the magnitude of the electromagnetic force.

An electromagnetic force nozzle based on MEMS technology of the present invention has electrode pairs, which are located at the front and rear ends of the nozzle hole, and are perpendicular to the electromagnetic pole formed by the conductive coil in the same plane. The purpose is that the electromagnetic field generated after electrification acts on the The conductive fluid forms a vertical downward electromagnetic force to complete the spraying process.

In the electromagnetic force nozzle based on the MEMS technology of the present invention, after being energized, the conductive fluid flows through the control chip and silicon material on the upper part of the nozzle, enters the soft magnetic material, and is ejected from the tapered nozzle hole at the bottom of the nozzle under the action of electromagnetic force .

According to above-mentioned inventive concept, the present invention adopts following technical scheme:

An electromagnetic force nozzle based on MEMS technology, including a conductive coil, a soft magnetic material, a silicon material, a control chip, a conductive fluid, and an electrode pair; the conductive coil is placed inside the soft magnetic material, and the silicon material is coated with a soft magnetic material material, the positive and negative poles of the conductive coil are respectively connected to the positive and negative poles of the electrode pair, the control chip is placed on the top of the silicon material, and the conductive fluid flows out from the bottom of the nozzle hole that runs through the control chip, silicon material, and soft magnetic material , the electrode pair runs through the soft magnetic material, silicon material and is connected to the control chip on the top, so as to realize the micro-flow control of the conductive fluid.

The conductive coil includes two positive terminals and two negative terminals; the coil at the left end of the nozzle hole is formed by a number of conductive coils connected in series, and the coil at the right end of the nozzle hole is formed by a number of conductive coils connected in series; The same direction electromagnetic pole of S right N; the positive terminal of the conductive coil formed by the left end connected in series is connected with the positive pole of the electrode pair, the negative terminal of the conductive coil formed by the left end connected in series is connected with the negative electrode of the electrode pair; the conductive coil formed by the right end connected in series The positive pole terminal is connected to the positive pole of the electrode pair, the negative pole terminal of the conductive coil formed in series by the right end is connected to the negative pole of the electrode pair, and the electromagnetic pole and the electric field share a pair of positive and negative electrodes.

The soft magnetic material covers the conductive coil, and the electromagnetic field formed after electrification is confined inside the soft magnetic material and will not leak to the outside of the soft magnetic material; there is a nozzle hole in the middle of the soft magnetic material to flow conductive fluid, and the nozzle hole is composed of conductive coils There is an electric field composed of electrode pairs before and after the nozzle hole.

There is a nozzle hole in the middle of the control chip to flow conductive fluid, the bottom is connected to the silicon material, the top is connected to an external power supply, and the built-in circuit controls the magnitude of the electromagnetic force; the positive and negative poles of the control chip are connected to the electrode pair through the silicon material and soft magnetic material to realize Conductive pathway.

The electrode pair is located at the front and rear ends of the nozzle hole, and the electromagnetic pole formed by the conductive coil is perpendicularly distributed in the same plane. The electromagnetic field generated after electrification acts on the conductive fluid to form a vertical downward electromagnetic force to drive the conductive fluid. (5) Complete the spraying process.

Compared with prior art, advantage of the present invention is as follows:

1. An electromagnetic spray head based on MEMS technology of the present invention is manufactured by MEMS technology, and the microstructure and control circuit are integrated on the same silicon substrate. The device is small in size, high in integration, good in combination, and high in spraying accuracy .

2. An electromagnetic force nozzle based on MEMS technology of the present invention drives the conductive fluid to flow directionally according to the electromagnetic force generated by the electromagnetic field acting on the conductive fluid. Compared with other driving methods, it has no noise, no heat, no vibration, and no driving mechanism , high repeatability, high reliability, high control precision, high injection efficiency.

3. An electromagnetic force nozzle based on MEMS technology of the present invention, the electromagnetic poles generated after the conductive coils in series are energized replace the permanent magnetic poles, avoiding other problems caused by the placement of permanent magnetic poles, and can adjust the magnetic field strength and electromagnetic driving force, Precisely control the flow rate of conductive fluids.

4. An electromagnetic force nozzle based on MEMS technology of the present invention, the electric field and the electromagnetic pole share a pair of positive and negative poles, and the direction of the current is changed, and the direction of the electric field and magnetic field is changed at the same time, so the direction of the electromagnetic force remains unchanged, which is beneficial to circuit design. wiring and controls.

5. An electromagnetic spray head based on MEMS technology of the present invention, its soft magnetic material covers the conductive coil, and the electromagnetic field formed after electrification is confined inside the soft magnetic material and will not leak to the outside of the soft magnetic material.

6. An electromagnetic spray head based on the MEMS process of the present invention, its control chip integrates the control circuit, soft magnetic material, conductive coil, etc. on the silicon material substrate through the MEMS process to form an independent and complete spraying unit. It is beneficial to the integrated manufacturing and joint control of multiple spraying units, reduces the volume of the spraying head, and increases the reliability of control.

Description of drawings

Fig. 1 is a schematic diagram of the structure of the electromagnetic force nozzle based on the MEMS process.

Fig. 2 is a schematic diagram of a soft magnetic material.

Fig. 3 is a schematic diagram of a conductive coil and an electrode pair.

Figure 4 is a schematic diagram of silicon material.

Figure 5 is a schematic diagram of the working principle.

detailed description

The present invention will be further described in detail below in conjunction with specific embodiments and accompanying drawings.

As shown in Figures 1 to 4, a MEMS technology-based electromagnetic force nozzle includes a conductive coil 1, a soft magnetic material 2, a silicon material 3, a control chip 4, a conductive fluid 5, and an electrode pair 6; the conductive coil 1 Placed inside the soft magnetic material 2, the silicon material 3 covers the soft magnetic material 2, the positive and negative poles of the conductive coil 1 are respectively connected to the positive and negative poles of the electrode pair 6, and the control chip 4 is placed in the silicon material 3 at the top, the conductive fluid 5 flows out from the bottom of the spray hole that penetrates the control chip 4, silicon material 3, and soft magnetic material 2, and the electrode pair 6 penetrates the soft magnetic material 2, silicon material 3 and is connected to the control chip 4 on the top, The micro flow control of the conductive fluid 5 is realized.

The conductive coil 1 includes two positive terminals 1-1 and two negative terminals 1-2; the coil at the left end of the injection hole is formed by connecting several conductive coils 1 in series, and the coil at the right end of the injection hole is formed by connecting several conductive coils 1 in series. After electrification, the left and right two groups of conductive coils 1 form the same electromagnetic poles of left S and right N; the positive terminal 1-1 of the conductive coil 1 formed by the left end is connected with the positive pole of the electrode pair 6, and the conductive coil 1 negative pole formed by the left end connected in series The terminal 1-2 is connected to the negative pole of the electrode pair 6; the positive terminal 1-1 of the conductive coil 1 connected in series at the right end is connected with the positive pole of the electrode pair 6, and the negative terminal 1-2 of the conductive coil 1 formed in series at the right end is connected with The negative poles of the electrode pair 6 are connected, and the electromagnetic pole and the electric field share a pair of positive and negative electrodes.

The soft magnetic material 2 covers the conductive coil 1, and the electromagnetic field formed after electrification is confined inside the soft magnetic material 2 and will not leak to the outside of the soft magnetic material 2; there is a nozzle hole in the middle of the soft magnetic material 2 to flow the conductive fluid 5, and the spray There are electromagnetic poles composed of conductive coils 1 on the left and right of the hole, and an electric field composed of electrode pairs 6 before and after the nozzle hole.

There is a nozzle hole in the middle of the control chip 4 to flow the conductive fluid 5, the bottom is connected to the silicon material 3, the top is connected to an external power supply, and the built-in circuit controls the magnitude of the electromagnetic force; the positive and negative poles of the control chip 4 pass through the silicon material 3 and the soft magnetic material 2 Connect with the electrode pair 6 to realize the conductive path.

The electrode pair 6 is located at the front and rear ends of the nozzle hole, and the electromagnetic pole formed by the conductive coil 1 is vertically distributed in the same plane, and the electromagnetic field generated after electrification acts on the conductive fluid 5 to form a vertical downward electromagnetic force. The conductive fluid 5 is driven to complete the spraying process.

As shown in Figure 5, the operating principle of the present invention is briefly described as follows:

The theory of electromagnetism points out that the force experienced by a moving charge in a magnetic field is called the Lorentz force, that is, the force that a magnetic field exerts on a moving charge. The Lorentz force is always perpendicular to the plane determined by the direction of the velocity of the charge and the direction of the magnetic field, that is, the moving charge deflects along the direction of the Lorentz force. The Lorentz force applies to both microscopically charged and macroscopically charged particles. The Ampere's force on the current element in the magnetic field is the macroscopic expression of the Lorentz force on the moving charges. Electromagnetic guns and maglev trains are both practical applications of the Lorentz force (Ampere force) on a macro scale.

In the present invention, vertically distributed electromagnetic poles (conductive coil 1 ) and electrode pairs 6 are arranged on the channel wall of the conductive fluid inside the nozzle. Connect the external power supply, the control chip 4 issues control commands according to the set parameters, the conductive coil 1 inside the nozzle generates an electromagnetic field, the direction of the electric field and the magnetic field is orthogonal and perpendicular to the conductive fluid 5, and the electromagnetic field forms a direction parallel to the flow direction of the conductive fluid 5. The electromagnetic force drives the conductive fluid 5 to be ejected from the nozzle.

According to the definition of Lorentz force, for a conductor with a length L, when the electric field E and magnetic field B acting on the conductor are orthogonal (perpendicular), the formula of the Lorentz force (Ampere force) on the conductor is: , that is, the magnitude of the Lorentz force is related to the length of the conductor, the loaded current and the strength of the magnetic field.

In the present invention, the length L of the conductor depends on the length of the electrode pair 6 in contact with the conductive fluid 5, the magnetic field strength B depends on the number of turns and the current size of the conductive coil 1, and the loaded current I depends on the voltage of the electrode pair 6 and the conductive fluid. The resistance ratio of 5, from which the Lorentz force F can be calculated. Therefore, controlling the Lorentz force can realize the motion control and flow control of the conductive fluid 5 .

Claims (5)

1. a kind of electromagnetic force shower nozzle based on MEMS technology, it is characterised in that including conductive coil（1）, soft magnetic material（2）、 Silicon materials（3）, control chip（4）, conductor fluid（5）, electrode pair（6）；The conductive coil（1）It is placed in soft magnetic material（2） Inside, the silicon materials（3）Cladding soft magnetic material（2）, the conductive coil（1）Both positive and negative polarity respectively with electrode pair（6） Both positive and negative polarity connection, the control chip（4）It is placed in silicon materials（3）Top, the conductor fluid（5）From through control chip （4）, silicon materials（3）, soft magnetic material（2）Spray orifice bottom outflow, the electrode pair（6）Through soft magnetic material（2）, silicon material Material（3）With the control chip at top（4）Connection, realizes to conductor fluid（5）Microfluidic control.

2. the electromagnetic force shower nozzle based on MEMS technology according to claim 1, it is characterised in that the conductive coil（1） Including two positive terminals（1-1）, two negative terminals（1-2）；Spray orifice left end coil is by some conductive coils（1）Series connection Form, spray orifice right-hand member coil is by some conductive coils（1）It is in series, the two groups of conductive coils in left and right after energization（1）Form left S right The electromagnetic pole in the same direction of N；The conductive coil that left end is in series（1）Positive terminal（1-1）With electrode pair（6）Positive pole be connected, The conductive coil that left end is in series（1）Negative terminals（1-2）With electrode pair（6）Negative pole be connected；What right-hand member was in series Conductive coil（1）Positive terminal（1-1）With electrode pair（6）Positive pole be connected, the conductive coil that right-hand member is in series（1）Negative pole Terminals（1-2）With electrode pair（6）Negative pole be connected, electromagnetic pole and electric field share a pair of positive and negative.

3. the electromagnetic force shower nozzle based on MEMS technology according to claim 1, it is characterised in that the soft magnetic material （2）Coated with conductive coil（1）, the electromagnetic field of formation is constrained on soft magnetic material after energization（2）Inside, will not be leaked to soft magnetism Property material（2）It is outside；Soft magnetic material（2）There is spray orifice circulation conductor fluid centre（5）, spray orifice or so has conductive coil（1）Group Into electromagnetic pole, have electrode pair before and after spray orifice（6）The electric field of composition.

4. the electromagnetic force shower nozzle based on MEMS technology according to claim 1, it is characterised in that the control chip（4） There is spray orifice circulation conductor fluid centre（5）, bottom connection silicon materials（3）, top connection external power source, built-in circuit control electricity The size of magnetic force；Control chip（4）Both positive and negative polarity pass through silicon materials（3）And soft magnetic material（2）With electrode pair（6）Connection, it is real Existing conductive path.

5. the electromagnetic force shower nozzle based on MEMS technology according to claim 1, it is characterised in that the electrode pair（6）Position In spray orifice rear and front end, with conductive coil（1）The orthogonal vertical distribution in approximately the same plane of the electromagnetic pole of formation, produces after energization Electromagnetic field effect in conductor fluid（5）, electromagnetic force straight down is formed, drive conductor fluid（5）Complete course of injection.