Electro-hydraulic pump head assembly with gas flow passage - Patents.com

Abstract

The present invention relates to an electrohydraulic pump head assembly, and more particularly to an electrohydraulic (EHD) pump head assembly having a gas flow passage for dispensing a viscous solution through a nozzle by applying a potential difference to the viscous solution. The electrohydraulic pump head assembly having a gas flow passage of the present invention has an effect of easily adjusting the conditions for dispensing a viscous solution by an EHD pump to improve dispensing quality. The electrohydraulic pump head assembly having a gas flow passage of the present invention has an effect of stably maintaining the dispensing quality of an electrohydraulic pump head assembly having a gas flow passage for dispensing a viscous solution.

Description

[Technical field]

[0001] The present invention relates to an electrohydraulic pump head assembly, and more particularly to an electrohydraulic (EHD) pump head assembly having a gas flow passage that applies a potential difference across a viscous solution to dispense the viscous solution through a nozzle. [Background technology]

[0002] Pumps that dispense viscous solutions at high speeds and in fixed quantities are widely used in a variety of technical fields, including semiconductor processing.

[0003] Pumps for dispensing such viscous solutions are available in a variety of forms and structures, including Auger pumps, pneumatic pumps, piezo pumps, and inkjet pumps.

[0004] Electro-hydrodynamic (EHD) pumps may be used to more precisely control the dispense volume of viscous solutions and dispense fine linewidth patterns onto the material.

[0005] An electrohydraulic pump is a pump that discharges a viscous solution stored in a reservoir through a nozzle using energy generated by an electric field generated by applying a high voltage to the viscous solution.

[0006] Although such electrohydraulic pumps are capable of dispensing viscous solutions in minute volumes, they have the disadvantage that the dispensing characteristics are significantly affected by factors such as the viscosity of the solution, the surrounding environment, and the shape of the electrodes.

[0007] Therefore, in order to be effectively used in various fields such as semiconductor processing, an electro-hydraulic pump head assembly is required that has a gas flow path structure that can easily dispense even viscous solutions with relatively high viscosity and that can relatively easily control the ejection shape, pattern, flow rate, etc. of the viscous solution while maintaining stable dispensing characteristics. Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention has been made to solve the above-mentioned problems, and its object is to provide an electro-hydraulic pump head assembly with a gas flow path, which has excellent performance in dispensing viscous solutions, while maintaining stable dispensing characteristics, and has a structure that allows the dispensing characteristics to be easily adjusted. [Means for solving the problem]

[0009] In order to achieve the above object, the electrohydraulic pump head assembly with a gas flow path of the present invention is characterized by including a storage section in which a viscous solution is stored, an insulating nozzle made of an insulating material connected to the storage section and extending in a longitudinal direction so as to discharge the viscous solution, an internal electrode arranged on a path along which the viscous solution stored in the storage section is transmitted to the insulating nozzle, and an external electrode formed to enclose at least a portion of the insulating nozzle and extending upward and downward. Effect of the Invention

[0010] The electrohydraulic pump head assembly with gas flow passages of the present invention has the advantage that the conditions under which the EHD pump dispenses viscous solutions can be easily adjusted to improve the dispense quality.

[0011] The electrohydraulic pump head assembly with a gas flow passage of the present invention has an effect of stably maintaining the dispensing quality of the electrohydraulic pump head assembly with a gas flow passage for dispensing a viscous solution. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a perspective view of an electro-hydraulic pump head assembly with a gas flow path according to one embodiment of the present invention. [Diagram 2] FIG. 2 is a front view of an electro-hydraulic pump head assembly with the gas flow path shown in FIG. 1. [Diagram 3] FIG. 2 is a front view of an electro-hydraulic pump head assembly with the gas flow path shown in FIG. 1. [Figure 4] 4A and 4B are a cross-sectional view and a partially enlarged view, respectively, of an electro-hydraulic pump head assembly having a gas flow passage shown in FIG. 1 taken along line IV-IV. [Diagram 5] 4A and 4B are a cross-sectional view and a partially enlarged view, respectively, of an electro-hydraulic pump head assembly having a gas flow passage shown in FIG. 1 taken along line IV-IV. [Figure 6] FIG. 2 is a front view of a portion of the electro-hydraulic pump head assembly with the gas flow path shown in FIG. 1. [Figure 7] 2 is an enlarged cross-sectional view of a portion of an electro-hydraulic pump head assembly including the gas flow passages shown in FIG. 1. [Figure 8] 2 is a diagram for explaining a state in which the electro-hydraulic pump head assembly having the gas flow passage shown in FIG. 1 is attached to a dispenser and used. FIG. [Figure 9] 2A-2C show alternative configurations for the external electrodes of the electrohydraulic pump head assembly shown in FIG. 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An electro-hydraulic pump head assembly with a gas flow path according to an embodiment of the present invention will now be described with reference to the accompanying drawings.

[0014] The electrohydraulic pump head assembly with gas flow passage of the present invention is for applying a viscous solution to a material placed on a base. When a voltage is applied to the viscous solution with the material placed on the grounded base, the viscous solution is ejected onto the material through a nozzle due to the potential difference between the base and the viscous solution.

[0015] FIG. 1 is a perspective view showing an electro-hydraulic pump head assembly with a gas flow path according to one embodiment of the present invention, FIGs. 2 and 3 are front views of the electro-hydraulic pump head assembly with the gas flow path shown in FIG. 1, and FIGs. 4 and 5 are a cross-sectional view and a partially enlarged view, respectively, of the electro-hydraulic pump head assembly with the gas flow path shown in FIG. 1 taken along line IV-IV.

[0016] 1 to 5, the electrohydraulic pump head assembly with gas flow passage according to the present embodiment includes a reservoir 110, an inner electrode 310, an insulating nozzle 330 and an outer electrode 350. As shown in FIG.

[0017] The storage unit 110 is configured to store a viscous solution to be discharged through the insulating nozzle 330. The storage unit 110 may be configured in various forms capable of storing a viscous solution. A storage unit that transfers a viscous solution stored in a separate container through a pipe such as a tube may also be used. In this embodiment, as shown in Figs. 1 to 5, a case in which the storage unit 110 formed in a cylindrical cartridge-shaped container structure is used will be described as an example. An air pressure regulator that can apply pressure to the viscous solution stored therein may be connected to the storage unit 110.

[0018] 4 and 5, an internal electrode 310 is installed at the lower end of the storage unit 110. The internal electrode 310 is made of a conductive material so that a voltage can be applied to the viscous solution stored in the storage unit 110. In this embodiment, the internal electrode 310 is formed in the shape of a metal tube having a constant inner diameter and thickness along the longitudinal direction. With this structure, the internal electrode 310 can apply a voltage to the viscous solution stored in the storage unit 110 and deliver the viscous solution to the insulating nozzle 330.

[0019] The insulating nozzle 330 is provided to extend in the longitudinal direction, as shown in Figures 4, 5 and 7. It is preferable that at least a portion of the insulating nozzle 330 is formed so that the inner diameter decreases toward the bottom. In this embodiment, as shown in Figure 7, the insulating nozzle 330 is formed in a tubular shape with an upper portion having a constant inner diameter along the longitudinal direction and a lower portion having an inner diameter decreasing toward the bottom.

[0020] The insulating nozzle 330 is made of an insulating material such as glass. In this embodiment, the insulating nozzle 330 is manufactured by drawing a glass tube. The insulating nozzle 330 is assembled to the lower end of the storage unit 110, similar to the internal electrode 310.

[0021] In this embodiment, the insulating nozzle 330 is assembled to the storage unit 110 with the internal electrode 310 inserted therein, as shown in FIG. 7. Preferably, the insulating nozzle 330 is assembled to the storage unit 110 by a screwing method while being coupled to a nut-shaped synthetic resin structure. At this time, the insulating nozzle 330 is connected to the storage unit 110 with the internal electrode 310 protruding from the lower end of the storage unit 110 inserted into the insulating nozzle 330. With this structure, the internal electrode 310 can apply a voltage to the viscous solution and directly supply the viscous solution to the insulating nozzle 330. In this embodiment, as shown in FIG. 7, the internal electrode 310 is formed to be inserted only up to the upper part of the insulating nozzle 330 where the inner diameter is formed to be constant. With this structure, the internal electrode 310 can apply a voltage to the viscous solution while delivering the viscous solution to a position very close to the outlet of the insulating nozzle 330.

[0022] It is preferable that the gap between the inner diameter of the insulating nozzle 330 and the outer diameter of the internal electrode 310 is as narrow as possible. By narrowing the gap between the inner diameter of the insulating nozzle 330 and the outer diameter of the internal electrode 310, the viscous solution can be effectively discharged through the insulating nozzle 330 while reducing the loss of pressure and electromagnetic force transmitted to the insulating nozzle 330.

[0023] Preferably, the distance between the inner diameter of the insulating nozzle 330 and the outer diameter of the internal electrode 310 is 0.05 mm to 0.1 mm. If the distance between the inner diameter of the insulating nozzle 330 and the outer diameter of the internal electrode 310 is smaller than 0.05 mm, it is difficult to assemble the insulating nozzle 330 and the internal electrode 310, and if the distance between the inner diameter of the insulating nozzle 330 and the outer diameter of the internal electrode 310 is larger than 0.1 mm, the viscous solution may flow between the insulating nozzle 330 and the internal electrode 310, or bubbles may be formed between the inner wall of the insulating nozzle 330 and the outer wall of the internal electrode 310, or bubbles may be discharged from the insulating nozzle 330 together with the viscous solution.

[0024] The insulating nozzle 330, the internal electrode 310, and the storage unit 110 are assembled to the upper body 210. The upper body 210 is configured to support the assembly of the storage unit 110, the internal electrode 310, and the insulating nozzle 330. The upper body 210 is assembled with the lower body 230 for use.

[0025] 4 and 5, the lower body 230 has an assembly hole 231 extending vertically. The upper body 210 has an assembly extension 211 formed in a shape corresponding to the assembly hole 231. The upper body 210 and the lower body 230 are assembled to each other in such a manner that the assembly extension 211 of the upper body 210 is inserted into the assembly hole 231 of the lower body 230.

[0026] The external electrode 350 is fixed to the lower body 230. That is, the external electrode 350 is installed and supported by the lower body 230. The external electrode 350 of this embodiment is formed in a tubular shape extending vertically. In this embodiment, the external electrode 350 is formed in a structure in which the inner diameter and thickness are constant along the vertical direction, but the structure and shape of the external electrode 350 can be modified in various ways. For example, the external electrode may be formed in a tubular structure in which the inner diameter of the external electrode increases or decreases along the vertical direction. Also, as shown in FIG. 9, it is possible to use an external electrode 360 ​​consisting of a plurality of external electrode elements 361 arranged at regular angular intervals along the circumferential direction and extending in the longitudinal direction.

[0027] When the assembly extension 211 is inserted into the assembly hole 231 to assemble the upper body 210 and the lower body 230, the external electrode 350 surrounds at least a portion of the outer periphery of the insulating nozzle 330 in a non-contact state. In this embodiment, as shown in Fig. 5, the end of the insulating nozzle 330 is inserted into the external electrode 350. At this time, the internal electrode 310 inserted into the insulating nozzle 330 is also inserted into the external electrode 350.

[0028] In this state, the upper body 210 is installed so as to be movable up and down with respect to the lower body 230. In this embodiment, the upper body 210 is installed so as to be movable up and down with respect to the lower body 230 along a guide rail installed on the lower body 230. The electro-hydraulic pump head assembly with a gas flow passage of this embodiment is configured to fix the height of the upper body 210 using a separate fixing member 250 after manually adjusting the height of the upper body 210. In some cases, it is also possible to configure the electro-hydraulic pump head assembly with a gas flow passage so as to automatically lift and lower the upper body 210 with respect to the lower body 230 by installing a lifting member in the form of a linear motor capable of adjusting the height of the upper body 210 according to a control signal. When the height of the upper body 210 is adjusted by such a lifting member, the height of the insulating nozzle 330 with respect to the external electrode 350 is adjusted as a result.

[0029] The electrohydraulic pump head assembly with gas flow passage of this embodiment includes a gas flow passage 410 connected between the insulating nozzle 330 and the outer electrode 350. The gas flow passage 410 is connected between the insulating nozzle 330 and the outer electrode 350 so as to transmit gas at positive or negative pressure between the insulating nozzle 330 and the outer electrode 350.

[0030] The gas flow passage 410 is connected to an external air pressure device through the inside of the lower body 230 between the insulating nozzle 330 and the external electrode 350. In this embodiment, the gas flow passage 410 passes through a path between the assembly extension 211 of the upper body 210 and the assembly hole 231 of the lower body 230.

[0031] The assembly hole 231 is formed in a cylindrical shape, and the assembly extension 211 is formed in a columnar shape with an outer diameter that fits the assembly hole 231 perfectly. Groove-shaped partial flow paths 213 that extend up and down at equal intervals (90 degree intervals) along the circumferential direction are formed on the outer surface of the assembly extension 211. A ring groove 215 that is formed in a ring shape along the outer diameter of the assembly extension 211 is formed at the upper end of the partial flow paths 213 and is connected to the assembly hole 231. The gas flow path 410 is connected between the assembly extension 211 and the assembly hole 231 along a path formed by the partial flow paths 213 and the ring groove 215. The gas flow path 410 extends from the ring groove 215 in the lateral direction of the lower main body 230. The gas flow path 410 is connected to an external pneumatic device via such a path.

[0032] When the external air pressure device generates a positive pressure, compressed gas is injected between the external electrode 350 and the insulating nozzle 330. Conversely, when the external air pressure device generates a negative pressure, the pressure between the external electrode 350 and the insulating nozzle 330 is reduced, and air around the insulating nozzle 330 is sucked in through the gas flow passage 410.

[0033] Meanwhile, the relative position of the insulating nozzle 330 with respect to the external electrode 350 is automatically aligned as the assembly extension 211 of the upper body 210 is inserted into the assembly hole 231 of the lower body 230. If the tolerance between the assembly extension 211 and the assembly hole 231 is machined to be very small, the horizontal displacement of the insulating nozzle 330 is fixed after the assembly extension 211 is inserted into the assembly hole 231. Therefore, when the assembly extension 211 is inserted into the assembly hole 231 and slides while being guided by the assembly hole 231, the insulating nozzle 330 easily enters the inside of the external electrode 350. In this manner, damage to the insulating nozzle 330 can be prevented. The insulating nozzle 330 is formed of a brittle glass material, which is very thin and long, and is easily broken even by a small impact. As described above, the insulating nozzle 330 easily enters the inside of the external electrode 350 due to the shape and structure of the assembly hole 231 and the assembly extension 211. When the upper body 210 and the lower body 230 are assembled with the horizontal position of the insulating nozzle 330 aligned with respect to the external electrode 350, the insulating nozzle 330 can easily enter the inside of the external electrode 350 while preventing damage to the insulating nozzle 330.

[0034] For this reason, it is preferable that the length of the insulating nozzle 330 protruding below the upper body 210 is shorter than the depth of the assembly hole 231. With this configuration, the assembly extension 211 starts to be inserted into the assembly hole 231 before the insulating nozzle 330 contacts the bottom of the assembly hole 231. As the assembly extension 211 is aligned by the assembly hole 231, the position of the insulating nozzle 330 is also automatically aligned.

[0035] As described above, the tolerance between assembly hole 231 and assembly extension portion 211 is very small, so that the gap between assembly hole 231 and assembly extension portion 211 in the remaining portion except for gas flow path 410 is airtight. If necessary, a seal member such as an O-ring can be provided in assembly extension portion 211 or assembly hole 231 to more reliably ensure airtightness between assembly hole 231 and assembly extension portion 211.

[0036] Meanwhile, an insulating cap 233 made of an insulating material is installed on the lower body 230. The insulating cap 233 has an electrode hole formed to penetrate vertically. The insulating cap 233 is coupled to the lower body 230 in a state in which the external electrode 350 can be placed inside the electrode hole. The insulating cap 233 serves to fix the external electrode 350 to the lower body 230 and to protect the operator from the high voltage applied to the external electrode 350.

[0037] The operation of an electro-hydraulic pump head assembly having a gas flow passage configured as described above will now be described.

[0038] First, a procedure for assembling the electro-hydraulic pump head assembly having a gas flow passage according to this embodiment will be described.

[0039] 1, 2 and 4, the external electrode 350 is assembled to the lower body 230. As described above, the external electrode 350 is fixed to the lower part of the lower body 230 using the insulating cap 233. At this time, the external electrode 350 is exposed to the lower side through the electrode hole of the insulating cap 233.

[0040] The external electrode 350 is electrically connected to a power supply device via the lower body 230. The power supply device applies a DC voltage to the external electrode 350 at a voltage set by a control unit.

[0041] Next, referring to Figs. 1, 2 and 7, the internal electrode 310 and the insulating nozzle 330 are assembled to the storage unit 110. The viscous solution stored in the storage unit 110 is ready to be discharged to the outside through the internal electrode 310. Also, as shown in Fig. 7, the insulating nozzle 330 is assembled to the storage unit 110 so that the internal electrode 310 is inserted up to a portion of the insulating nozzle 330 where the inner diameter is formed to be constant. In this state, the viscous solution stored in the storage unit 110 can be directly transferred to the insulating nozzle 330 through the internal electrode 310. An air pressure regulator is connected to the storage unit 110. The air pressure regulator can apply pressure to the viscous solution stored in the storage unit 110 at a pressure set by a control unit.

[0042] In this state, the assembly of the storage unit 110, the internal electrode 310, and the insulating nozzle 330 is attached to the upper body 210, as shown in Figures 1 and 2. As shown in Figures 1 and 2, the storage unit 110 and its peripheral configuration are attached to the upper body 210 with the upper body 210 raised relative to the lower body 230. With the upper body 210 raised in this manner, the internal electrode 310 and the insulating nozzle 330 can be easily attached to the upper body 210 without getting caught on the lower body 230.

[0043] The internal electrode 310 is connected to a power supply device via the upper body 210. The power supply device applies a DC voltage set by a control unit to the internal electrode 310.

[0044] When the upper body 210 is slid downward, the assembly extension 211 is inserted into the assembly hole 231, and the upper body 210 and the lower body 230 are assembled to each other, as shown in Figures 3 and 5. At this time, the insulating nozzle 330 is also inserted into the inside of the external electrode 350. This process can be performed manually or by a lifting member operated by a signal from a control unit. The relative position between the upper body 210 and the lower body 230 can be adjusted according to various parameters such as working conditions and properties of the viscous solution.

[0045] As described above, when the length of the insulating nozzle 330 protruding downward from the upper body 210 is formed shorter than the depth of the assembly hole 231, there is an advantage in that the risk of damage to the assembly hole 231 can be reduced. Since the assembly extension part 211 starts to be inserted into the assembly hole 231 before the insulating nozzle 330 contacts the bottom of the assembly hole 231 or before it enters the inside of the outer electrode 350, the position of the assembly extension part 211 is aligned by the assembly hole 231, and the position of the insulating nozzle 330 is also automatically aligned. Therefore, the insulating nozzle 330 enters the inside of the outer electrode 350 at an accurate position. In addition, during the process of the insulating nozzle 330 entering, the insulating nozzle 330 does not come into contact with the outer electrode 350.

[0046] 6, when the assembly of the upper body 210 and the lower body 230 is completed, the end of the insulating nozzle 330 is exposed below the external electrode 350. In some cases, by adjusting the height of the upper body 210, it is possible to perform a dispensing operation in a state where the end of the insulating nozzle 330 is not exposed below the external electrode 350.

[0047] The electro-hydraulic pump head assembly with a gas flow path of this embodiment assembled and used in the above-mentioned order can be used in the state shown in Fig. 8. As shown in Fig. 8, the electro-hydraulic pump of this embodiment is installed on a support panel together with other components such as a camera and a sensor, and is installed on a separate transfer device for use. While being transferred vertically and horizontally by the transfer device, the viscous solution is dispensed in various ways onto the material placed at the bottom.

[0048] As described above, when a material is placed on the grounded base (bottom) and a DC voltage is applied to the internal electrode 310 and the external electrode 350 by a power supply device, the viscous solution in the insulating nozzle 330 is discharged downward due to a potential difference with respect to the base generated by the internal electrode 310 and the external electrode 350. In this embodiment, a constant DC voltage is applied to the internal electrode 310 and pulse voltages of various patterns and frequencies are applied to the external electrode 350 to discharge the viscous solution through the insulating nozzle 330. In some cases, it is also possible to configure an electrohydraulic pump head assembly having a gas flow path by applying a constant DC voltage to the external electrode 350 and a pulse voltage of a specific frequency to the internal electrode 310.

[0049] As shown in Fig. 7, the internal electrode 310 penetrates into the insulating nozzle 330, so that a DC voltage can be applied more effectively to eject the viscous solution. This structure can improve the dispensing performance of the viscous solution. In addition, since the internal electrode 310 of this embodiment is formed in a tubular shape, it can form a potential difference and also supply the viscous solution to the insulating nozzle 330, so that the dispensing performance can be further improved.

[0050] Due to this structure between the internal electrode 310 and the insulating nozzle 330, the distance between the portion where the viscous solution stored in the reservoir 110 is supplied to the insulating nozzle 330 and the portion where the viscous solution is discharged from the insulating nozzle 330 can be made very close to each other. This structure can drastically reduce the possibility of bubbles being generated during the dispensing process. In addition, this structure applies a voltage to the viscous solution by the internal electrode 310 at a position very close to the discharge port of the insulating nozzle 330, so that the electrohydrodynamic pump head assembly with the gas flow path of this embodiment has excellent dispensing performance. In addition, this structure has the advantage that it is very easy to directly control the dispensing characteristics.

[0051] In addition, since the external electrode 350 can also be applied with a DC voltage at a position very close to the internal electrode 310 and the insulating nozzle 330, the electrohydraulic pump head assembly with a gas flow passage of the present embodiment has a better dispensing performance. In particular, in the electrohydraulic pump head assembly with a gas flow passage of the present embodiment, the external electrode 350 is formed in a tubular shape to enclose the outer periphery of the insulating nozzle 330 and form a space extending up and down. Since the DC voltage is applied to the external electrode 350 in this state, the electrohydraulic pump head assembly with a gas flow passage of the present invention can reduce the influence of interference from the external environment and noise. As a result, the electrohydraulic pump head assembly with a gas flow passage of the present invention has a more stable performance of dispensing a viscous solution.

[0052] In addition, when the internal electrode 310 and the external electrode 350 are formed in a cylindrical shape, the area and space in which a potential difference is generated between the internal electrode 310 and the external electrode 350 can be further expanded, so that the electrohydrodynamic pump head assembly with a gas flow path of the present invention has a structure that can transmit electromagnetic force more effectively to a viscous solution.

[0053] Next, the operation of the gas flow passage 410 will be described. The gas flow passage 410 connected to the external air pressure pump is connected to the lower parts of the upper body 210 and the lower body 230 through the ring groove 215 and the partial flow passage 213 formed in the assembly extension part 211. At the lower end of the partial flow passage 213, the gas flow passage 410 again extends radially along the radial direction and continues to the inner space of the external electrode 350. As a result, the end of the gas flow passage 410 is connected to the space between the external electrode 350 and the insulating nozzle 330. Depending on the operation of the external air pressure pump, the gas flow passage 410 supplies gas at positive or negative pressure between the external electrode 350 and the insulating nozzle 330.

[0054] Generally, a pump that dispenses a viscous solution generally performs a purge operation to remove internal air bubbles at the start of operation or during calibration. When performing such a purge operation, if a positive pressure is generated through the gas passage 410, it acts to help the viscous solution to be discharged through the insulating nozzle 330. In addition to the purge operation, when a dispensing operation for a product is started, if a gas flow with a certain pressure is generated around the insulating nozzle 330 through the gas passage 410, it is possible to reduce the time required to form a stable meniscus for dispensing.

[0055] By adjusting the magnitude of the gas pressure transmitted through the gas flow path 410 and the gas flow rate, the electro-hydraulic pump head assembly with the gas flow path of this embodiment can be operated to dispense a viscous solution in a spray shape rather than ejecting the viscous solution in droplet units.

[0056] Meanwhile, the electro-hydraulic pump head assembly with a gas passage may be operated so that a vacuum is formed around the insulating nozzle 330 by transmitting a negative pressure through the gas passage 410. When a negative pressure is generated in the gas passage 410 during the purging operation as described above, the viscous solution purged through the insulating nozzle 330 is sucked and discharged to the outside through the gas passage 410. That is, in the stage of calibrating the electro-hydraulic pump head assembly with a gas passage or preparing for the operation, the viscous solution is discharged to the outside through the gas passage 410 without dripping down the insulating nozzle 330, thereby preventing contamination of the working space by the viscous solution. Also, even when the viscous solution is dispensed in a spray form as described above, a negative pressure may be applied to the gas passage 410 so that fine particles of the viscous solution are sucked and discharged to the outside through the gas passage 410 while the viscous solution is not dispensed on the material.

[0057] In the electrohydrodynamic pump head assembly having the gas flow passage of this embodiment, the external electrode 350 is disposed to enclose the insulating nozzle 330 in a non-contact manner, which is advantageous in terms of structure in that the gas flow passage 410 can be easily connected between the insulating nozzle 330 and the external electrode 350. This structure allows the gas flow passage 410 to be located very close to the insulating nozzle 330, which is advantageous in that the effect of the positive or negative gas pressure transmitted to the gas flow passage 410 can be improved.

[0058] On the other hand, in a dispense pump such as an electrohydraulic pump head assembly with a gas flow passage of the present invention, it is very important to maintain the nozzle height at a set value. In the present invention, the height of the outer electrode 350 and the insulating nozzle 330 can be calibrated and controlled using the following method.

[0059] As shown in Figs. 1, 2 and 4, the upper body 210 is raised relative to the lower body 230, and the entire structure as shown in Fig. 7 is lowered to measure the height of the external electrode 350. When a Linear Variable Displacement Transducer (LVDT) sensor is used, the external electrode 350 is lowered until it contacts the LVDT sensor to grasp the reference height of the external electrode 350. The relative displacement of the internal electrode 310 or the insulating nozzle 330 with respect to the external electrode 350 can be easily measured or adjusted through the relative displacement between the upper body 210 and the lower body 230. Therefore, by directly measuring the height of the external electrode 350 in the above-mentioned manner and indirectly measuring the height of the internal electrode 310 or the insulating nozzle 330, it is possible to accurately grasp and adjust the height of the main components while preventing damage to the internal electrode 310 or the insulating nozzle 330. In this manner, it is possible to easily adjust factors related to the height of the main components to control the dispensing characteristics of the viscous solution.

[0060] Meanwhile, the electrohydraulic pump head assembly with a gas flow passage of the present embodiment has a structure in which the container-shaped storage part 110, the internal electrode 310, and the insulating nozzle 330 can be mounted on the upper body 210 as a set as described above, and has excellent usability and performance. In the past, a structure in which a viscous solution is stored in a container such as a vial and the viscous solution is delivered to a nozzle through a tube has been used, but in the present invention, a structure in which the container-shaped storage part 110, the internal electrode 310, and the insulating nozzle 330 are directly connected to each other in close proximity is used. As a result, the pressure loss of the regulator connected to the storage part 110 can be minimized while being delivered to the internal electrode 310. In addition, since no intermediate connection tube is used, the electrohydraulic pump head assembly with a gas flow passage of the present embodiment has the advantage of being simplified in structure and small in size.

[0061] The structure of the present invention can be modified in various ways while maintaining the above-mentioned advantages. Although it has been described above that the storage unit 110, the internal electrode 310, and the insulating nozzle 330 are attached to the upper body 210 in a state where they are assembled into a set, this structure can be modified as necessary. For example, it is also possible to configure the storage unit 110 to be connected to the internal electrode 310 and the insulating nozzle 330 by detachably connecting the storage unit 110 to the upper body 210 in a state where the internal electrode 310 and the insulating nozzle 330 are assembled to the upper body 210.

[0062] Although the present invention has been described above with reference to preferred embodiments, the scope of the present invention is not limited to the embodiments described above and illustrated in the drawings.

[0063] For example, the structures of the internal electrode 310, the insulating nozzle 330, and the external electrode 350 can be modified into various different structures other than a cylindrical structure. The outer and inner diameters can also be modified in various ways as necessary. In addition, the external electrode 360 ​​can be modified to have a similar structure to a cylindrical external electrode 360 ​​by using a plurality of external electrode elements 361 arranged in the circumferential direction, as shown in Fig. 9. The structure of the internal electrode 310 can also be modified into such a structure for use.

[0064] Also, unlike the structure described above with reference to the drawings, the electrohydrodynamic pump head assembly having the gas flow passage of the present invention can be configured such that the height of either the internal electrode or the insulating nozzle can be adjusted relative to the other. By adjusting the height between the internal electrode and the insulating nozzle in this manner, the dispensing characteristics of the viscous solution can be adjusted.

[0065] Although the inner electrode 310 is described above as being inserted inside the insulating nozzle 330, in some cases, it is possible to configure an electro-hydrodynamic pump head assembly having a gas flow passage in a form in which the inner electrode is not inserted into the insulating nozzle. In some cases, an inner electrode other than a tubular one may be used.

[0066] In addition, although the inner electrode 310 and the insulating nozzle 330 have been described and illustrated as being directly connected to the container-like reservoir 110, it is also possible to construct an electro-hydraulic pump head assembly having a gas flow path in which the container-like reservoir is connected to the inner electrode and the insulating nozzle via an intermediate structure such as a tube.

[0067] In addition, although the above-mentioned example shows a structure in which the upper body 210 is provided so as to be liftable and lowerable relative to the lower body 230, it is also possible to change to a structure in which the lower body is provided so as to be liftable and lowerable relative to the upper body. In this case, the lifting member lifts and lowers the lower body relative to the upper body.

[0068] In addition, the assembly structure of the upper and lower bodies may be modified in various ways, such as a structure in which the upper and lower bodies are screwed together or a structure in which the bodies are snapped together, rather than a structure in which the upper and lower bodies are separated from each other. It is also possible to configure an electro-hydraulic pump head assembly with a gas flow passage that includes a body portion that is integrally formed with the upper and lower bodies, rather than a structure in which the upper and lower bodies are separated from each other.

[0069] In addition, although the electro-hydraulic pump head assembly having a gas flow passage with a structure including the gas flow passage 410 has been described above as an example, the structure of the gas flow passage can be modified in various ways, and it is also possible to configure an electro-hydraulic pump head assembly having a gas flow passage with a structure that does not include a gas flow passage. The structure of the gas flow passage can also be modified into various forms other than the structure of the ring groove 215 and partial flow passages 213 described above. [Explanation of symbols]

[0070] 110 Storage 310 Internal electrode 330 Insulating nozzle 350 external electrode 210 Upper body 230 Lower body 211 Assembly extension 231 Assembly hole 213 Partial channel 215 Ring groove 250 Fixing member 233 Insulating Cap 410 Gas flow path 360 external electrode 361 External Electrode Element

Claims

1. a storage section in which the viscous solution is stored; an insulating nozzle made of an insulating material and connected to the storage unit and extending in a longitudinal direction so as to discharge the viscous solution; an internal electrode disposed on a path along which the viscous solution stored in the storage unit is transferred to the insulating nozzle; an external electrode formed to surround at least a portion of the insulating nozzle in a non-contact manner; a gas flow path connected between the insulating nozzle and an external electrode to transmit a gas under positive or negative pressure between the insulating nozzle and an external electrode; The electro-hydraulic pump head assembly, wherein the outer electrode includes a plurality of outer electrode elements arranged circumferentially about the insulating nozzle.

2. 2. The electro-hydraulic pump head assembly with gas flow passages as recited in claim 1, wherein said outer electrode is tubular in shape.

3. 3. The electro-hydraulic pump head assembly with gas flow passages as recited in claim 2, wherein said outer electrode is formed with a constant inner diameter along its length.

4. 3. The electro-hydraulic pump head assembly with gas flow passages as recited in claim 2, wherein said outer electrode is formed with an inner diameter that gradually decreases along a longitudinal direction.

5. An electro-hydraulic pump head assembly having a gas flow passage as described in any one of claims 1 to 4, further comprising a lower body coupled to the outer electrode to support the outer electrode and in which the gas flow passage is formed.

6. 6. The electro-hydraulic pump head assembly with gas flow passages as claimed in claim 5, further comprising an upper body assembled to said insulating nozzle for supporting said insulating nozzle.

7. The lower body has an assembly hole extending vertically, The upper body includes an assembly extension portion formed in a shape corresponding to the assembly hole, 7. The electro-hydrodynamic pump head assembly with gas flow path of claim 6, wherein the relative position of the insulating nozzle to the outer electrode is determined by inserting an assembly extension of the upper body into an assembly hole of the lower body.

8. 8. The electro-hydrodynamic pump head assembly with gas flow passages as described in claim 7, wherein a portion of the gas flow passage is formed between the upper body and the lower body and is connected between the insulating nozzle and an external electrode.

9. 8. The electro-hydrodynamic pump head assembly with a gas flow path as described in claim 7, wherein the assembly hole of the lower body is formed to guide the assembly extension of the upper body slidably up and down so that the insulating nozzle can be inserted into the external electrode while the position of the insulating nozzle is aligned with respect to the external electrode.

10. 10. The electro-hydraulic pump head assembly with gas flow path according to claim 9, wherein a length of the insulating nozzle protruding below the upper body is shorter than a depth of an assembly hole in the lower body.

11. 8. The electro-hydraulic pump head assembly including a gas flow passage as described in claim 7, wherein the assembly hole of the lower body and the assembly extension of the upper body are formed so that the remaining portions except for the gas flow passage are airtight to each other.

12. 8. An electro-hydraulic pump head assembly with a gas flow path as described in claim 7, wherein the gas flow path includes a plurality of partial flow paths extending vertically between an assembly extension of the upper body and an assembly hole of the lower body.

13. 13. The electro-hydraulic pump head assembly with gas flow passages as claimed in claim 12, wherein the plurality of partial flow passages are arranged at equal intervals along the outer periphery of the assembly extension of the upper body.

14. 6. The electro-hydraulic pump head assembly with a gas flow path as claimed in claim 5, further comprising an insulating cap made of an insulating material and coupled to a lower portion of the lower body, the insulating cap having an electrode hole formed therein so that the external electrode is disposed therein.

15. 7. The electro-hydraulic pump head assembly with a gas flow path according to claim 6, wherein one of the upper body and the lower body is provided so as to be able to rise and fall relative to the other.

16. 16. The electro-hydraulic pump head assembly with gas flow passages as claimed in claim 15, further comprising a lifting member for lifting one of the upper body and the lower body relative to the other.

17. 17. The electro-hydraulic pump head assembly with gas flow passages as claimed in claim 16, wherein the reservoir is formed in a container shape, and the inner electrode and the insulating nozzle are coupled to and installed in the reservoir.

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