KR20120041040A

KR20120041040A - Magnetostrictive inkjet head

Info

Publication number: KR20120041040A
Application number: KR1020100102612A
Authority: KR
Inventors: 박영우; 유재현
Original assignee: 충남대학교산학협력단
Priority date: 2010-10-20
Filing date: 2010-10-20
Publication date: 2012-04-30
Also published as: KR101186786B1

Abstract

PURPOSE: A magnetostrictive inkjet head is provided to prevent fluid denaturation due to high voltage or heat. CONSTITUTION: A magnetostrictive inkjet head comprises a housing, chamber(5), nozzle(7), magnetostrictive member(9), coil(11), permanent magnet(13), push rod(15), push rod head(17), and elastic member(19). The push rod sprouts fluid by pushing a push rod head. The magnetostrictive member is shorten in case of inflow of current.

Description

Magnetostrictive Inkjet Head {Magnetostrictive Inkjet Head}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetostrictive inkjet head capable of automatically performing a print job by computer control. In particular, a fluid filled in an inkjet head by using a magnetostrictive material whose appearance changes according to an ambient magnetic field is directed to the injection member. A magnetostrictive inkjet head capable of jetting with

In general, an inkjet printing technique is a technique of spraying droplets having a diameter of tens or hundreds (μm) to a desired position on the injection member, and more specifically, a fluid stored in the print head is sprayed on the injection member. It is a technique to inject a specific shape by spraying.

Such inkjet printing technology can use paper, fabric, metal, ceramic, polymer, etc. as the material to be sprayed, and the present invention is not only a display manufacturing process such as LCD and OLED, but also a PCB manufacturing process and a DNA microarray. The advantage is that the application range is wide, even in the bio field.

On the other hand, a method for discharging the fluid contained in the inkjet head to the outside of the nozzle provided in the inkjet head generally includes a thermal transfer method, an electrostatic method and the like.

In this case, the heat transfer method is a method of heating the fluid through the heater to generate bubbles in the fluid filled in the inkjet head to discharge the fluid filled in the inkjet head to the outside of the nozzle, the electrostatic force method is to apply a high voltage to the fluid and the injection member It is a technique that inscribes a desired shape on the injection target member by generating an attractive force on the applied fluid and the injection target member.

However, the above-described thermal transfer method and electrostatic force method have a problem in that the fluid may be denatured by applying heat or high voltage to the fluid, thereby limiting the available fluid.

On the other hand, in order to solve the above problems, there is a piezo method that can push the chamber to push the fluid stored in the chamber out of the nozzle, the piezo method is the length of the piezo element is increased or reduced in accordance with the external electrical signal By contacting one end with the chamber, the fluid filled in the chamber is pushed out of the nozzle.

However, the piezoelectric device has a problem in that it is not possible to exert various forces due to the characteristics of the device, and thus there is a limit in exporting droplets of various sizes to the outside of the nozzle.

Accordingly, the present invention solves the structural problems of the conventional inkjet head as described above to prevent the fluid filled in the inkjet head from being deteriorated due to high voltage or heat, and overcome the limitations of the self-deforming inkjet head using a conventional piezo element. It is an object of the present invention to provide a magnetostrictive inkjet head.

Self-deforming inkjet head of the present invention for achieving the above object is installed in the housing and the lower portion of the housing to temporarily store the fluid flowing from the outside and the top of the open chamber, the top is connected to the chamber A nozzle which is exposed at the lower end to the outside of the housing and sprays the fluid filled in the chamber toward the injection member, a magnetostrictive member which is lengthened or shortened in accordance with the strength of the surrounding magnetic field while being inserted and fixed inside the housing, and inside the housing It is provided with a coil which is fixed in addition to being installed outside the periphery of the magnetostrictive member and whose strength or direction of the magnetic field is changed in accordance with an electrical signal input from the outside.

In addition, a permanent magnet is installed between the housing and the coil or between the coil and the magnetostrictive member to generate a fixed strength and a magnetic field in a fixed direction, and an upper surface of the housing is aligned with a lower surface of the magnetostrictive member. Push rods are mounted and the bottom surface extends toward the chamber, and the bottom surface of the push rod is inserted into the chamber through the open top surface of the chamber so that fluid filled in the chamber does not flow into the housing. And, the push rod head which is moved in the vertical direction along the push rod may be mounted.

In addition, an inner side of the housing may be equipped with an elastic member that is fixed to the inner bottom of the housing, the top surface is fixed to any portion of the push rod to push the push rod in the direction of the magnetostrictive member at all times. .

In the magnetostrictive inkjet head according to the present invention having such a structure, when a current flowing in one direction is input to the coil, the push rod is lowered while the length of the magnetostrictive member is increased, and the fluid filled in the chamber is then push rod. It is pushed by the head and blows out of the nozzle.

On the other hand, when a current flowing in the other direction is input to the coil, the length of the magnetostrictive member is reduced, and the push rod is raised by the elastic restoring force of the elastic member, and at the same time, the fluid is refilled into the chamber. In addition, no fluid is sprayed out of the nozzle.

On the other hand, when a current flowing in the other direction is input to the coil, the length of the magnetostrictive member is reduced, and the push rod is raised by the elastic restoring force of the elastic member, and at the same time, the fluid is refilled into the chamber. ) do.

Accordingly, the magnetostrictive inkjet head according to the present invention may control the amount of fluid that is ejected out of the nozzle by varying the strength and direction of the current input to the coil, and may introduce the fluid stored in the external fluid tank into the chamber. It may be.

In addition, by using the magnetostrictive member as a power source for lowering the push rod, there is an advantage of not having to apply high voltage or high heat to the fluid introduced into the chamber.

In addition, the magnetostrictive member can exhibit a high driving force compared to the piezo element has the advantage that the application range is wide.

In addition, the magnetostrictive member has the advantage that it can respond faster to the input current than the existing piezoelectric element, there is an advantage that the frequency range of the input current is also wide.

1 is a longitudinal cross-sectional view of the present invention;
2a to 2c are views for explaining the operation of the present invention.

Hereinafter, with reference to the accompanying drawings will be described in detail the present invention.

As shown in FIG. 1, the magnetostrictive inkjet head according to the present invention has a housing 3 and a chamber 5 which temporarily stores fluid introduced from the outside while being installed in the lower portion of the housing 3 and whose top is open. Nozzle (7), the housing (3), the upper end of which is connected to the chamber (5) and the lower end is exposed out of the housing (3), and the fluid filled in the chamber (5) is sprayed in the direction of the injection member (6). The magnetically deformable member 9 which is inserted into and fixed in the inner side of the magnetic deformable member 9, the length of which increases or decreases according to the strength of the surrounding magnetic field, and is fixedly inserted into the inner side of the housing 3 and installed outside the circumference of the magnetically deformed member 9. A coil 11 is provided in which the strength of the magnetic field or the direction of the magnetic field is changed in accordance with an electrical signal input from the same.

In addition, a permanent magnet 13 is provided between the housing 3 and the coil 11 or between the coil 11 and the magnetostrictive member 9 to generate a fixed strength and a magnetic field in a fixed direction. Inside the housing 3, a push rod that is lowered when the upper surface is in contact with the lower surface of the magnetostrictive member 9 and the lower surface extends in the direction of the chamber 5 is extended in length. 15 is mounted, the lower end surface of the push rod 15 is inserted into the chamber 5 through the open upper surface of the chamber 5 and the fluid filled in the chamber 5 is filled inside the housing 3. A push rod head 17 may be mounted to move in an up and down direction along the push rod 15 so as not to flow in.

In addition, a lower end surface is fixed to an inner lower side of the housing 3 and an upper end surface is fixed to any part of the push rod 15 inside the housing 3 so that the push rod 15 is always deformed by a magnetostrictive member ( The elastic member 19 which pushes up in the 9) direction can be mounted.

In the magnetostrictive inkjet head according to the present invention having such a structure, when a current flowing in one direction is input to the coil 11, the push rod 15 is lowered while the length of the magnetostrictive member 9 is increased. Then, the fluid filled in the chamber 5 is pushed by the push rod head 17 to be discharged out of the nozzle (7).

On the other hand, when the current flowing in the other direction to the coil 11 is input, the length of the magnetostrictive member 9 is reduced, the push rod 15 is raised by the elastic restoring force of the elastic member 19 At the same time, the fluid is refilled into the chamber 5 and the fluid is not sprayed out of the nozzle 7.

In addition, as shown in FIG. 1, between the magnetostrictive member 9 and the coil 11, the shape of the coil 11 is preserved as it is, and from the coil 11 and the permanent magnet 13. A yoke 21 for directing the generated magnetic field and routing the magnetic field evenly inside the housing 3 may be mounted, and the upper and lower portions of the coil 11 may be coil 11 or permanent. The flux path part 23 made of a magnetic material may be provided so that the magnetic field generated from the magnet 13 flows through the upper portion of the coil 11 or the lower portion of the coil 11.

In addition, as shown in FIG. 1, the side of the push rod 15 may be provided with a hook hook 24 extending outward of the push rod 15.

At this time, the upper surface of the hook hook 24 is a positive pass portion 23 positioned below the coil 11 when the hook hook 24 is pushed up by the elastic member 19 in the direction of the magnetostrictive member 9. Can come in contact with

In addition, the upper end of the elastic member 19 may be in contact with the bottom surface of the locking hook 24 to push up the locking hook 24 in the direction of the positive pass portion 23 located below the coil 11.

In addition, a locking jaw 28 may be provided inside the housing 3 located above the chamber 5 to support the lower end of the elastic member 19.

Accordingly, when the elastic member 19 pushes the locking hook 24 while the lower end spans the locking jaw 28, the length of the magnetic deformation member 9 is reduced. Can be raised in the (9) direction.

In addition, a head gasket 25 is installed on the side circumferential surface of the push rod head 17 to prevent the fluid filled in the chamber 5 from leaking into the inside of the housing 3.

Meanwhile, as shown in FIG. 1, a lower portion of the housing 3 may be provided with a through hole 26 connected to the inside of the housing 3, and the through hole 26 may have an upper connector housing 27. ) May be mounted on the upper surface of the upper connector housing 27 facing the inner side of the housing 3, with the push rod head 17 fitted in the upper insertion hole to move in the vertical direction. 29 is dug in the inward direction of the upper connector housing 27 at the top surface of the upper connector housing 27.

In addition, as shown in FIG. 1, the push rod 15 and the push rod head extend straight from the edge of the upper insertion hole 29 toward the inner side of the housing 3 at the edge of the upper insertion hole 29. The guide tube 30 which can be moved in the up and down directions while the 17 is fitted can be mounted.

The guide tube 30 helps the push rod 15 and the push rod head 17 which are moved in the up and down directions not to deviate from a predetermined position inside the housing 3, and the top of the push rod 15. ? Having to move smoothly.

In addition, a chamber 5 in which fluid is stored may be installed inside the upper insertion hole 29, and the upper connector housing 27 may be installed in the upper connector housing 27 from a lower surface of the upper connector housing 27. A lower insertion hole 31 may be provided which is dug in the inner direction of the chamber 5 and communicates with each other.

In addition, a lower connector housing 33 may be installed in the lower insertion hole 31, and a fluid filled in the chamber 5 through a nozzle 7 communicating with the chamber 5 through the lower connector housing 33. Can be discharged out of the lower connector housing 33 through the nozzle 7, and a nozzle gasket 35 is mounted between the chamber 5 and the nozzle 7 so that the chamber 5 and the nozzle 7 can be discharged. It can prevent the fluid from leaking in between.

Meanwhile, as shown in FIG. 1, the upper connector housing 27 has a circumferential surface of the upper connector housing 27, an inner side of the upper connector housing 27, and an upper insertion as shown in FIG. 1. A tube insertion hole 37 may be provided that connects to the chamber 5 via a hole 29, and the tube insertion hole 37 facilitates coupling of the chamber 5 and the fluid transfer pipe 41. In addition, a fitting connector 39 may be mounted to prevent fluid from leaking from the fluid transfer pipe 41 or the chamber 5, and the fitting connector 39 may store fluid stored in the external fluid tank 40 in the chamber 5. It may be mounted to the fluid transfer pipe 41 to move.

In addition, a tubing gasket 43 may be mounted at a portion at which the fluid transfer pipe 41 and the chamber 5 are connected to prevent fluid from leaking from the connection portion between the fluid transfer pipe 41 and the chamber 5.

The operation of the magnetostrictive inkjet head according to the present invention having the above structure will be described below with reference to FIGS. 2A to 2C.

First, as shown in FIG. 2A, the magnetostrictive member 9 provided in the present invention is normally used in a magnetic field generated from the permanent magnet 13 provided in the present invention in which no current is input to the coil 11. By pressing the push rod 15 while deforming itself.

At this time, the fluid filled in the chamber 5 cannot escape to the outside of the nozzle 7.

On the other hand, when a current (positive current) flowing in one direction is applied to the coil 11 according to the present invention as shown in Fig. 2B, a magnetic field is generated around the coil 11, and the coil 11 The magnetic field generated from) is combined with the magnetic field generated from the permanent magnet 13, resulting in a strong change in the magnetic field strength around the magnetostrictive member 9.

At this time, the magnetostrictive member 9 is lengthened by the strengthened magnetic field, the push rod 15 which is in contact with the bottom surface of the magnetostrictive member 9 is pushed by the magnetostrictive member 9 chamber ( 5) will descend in the direction.

In addition, as the push rod 15 descends, the elastic member 19 is pressed by the catching hook 24 to contract.

In addition, the descending push rod 15 lowers the push rod head 17 integrally connected with the push rod 15, and the push rod head 17 inserted into the chamber 5 is a push rod. The fluid filled in the chamber 5 by being pushed by 15 is pushed out of the nozzle 7.

Therefore, the fluid out of the nozzle 7 injects an appropriate amount of fluid to the injection member 6 facing the nozzle 7.

On the other hand, when the current (negative current) flowing in the other direction is applied to the coil 11 according to the present invention as shown in Figure 2c, the direction of the magnetic field flowing around the coil 11 is changed, the permanent The magnetic field generated from the magnet 13 is weakened, and as a result, the strength of the entire magnetic field formed inside the housing 3 is weakened.

Therefore, the magnetostrictive member 9 is reduced in length by the weakened magnetic field, and the retracted elastic member 19 pushes up the catching hook 24 to raise the push rod 15.

In addition, the push rod head 17 integrally coupled with the push rod 15 rises upward in the chamber 5 from the inside of the chamber 5, thereby lowering the pressure inside the chamber 5.

Therefore, the fluid filled in the chamber 5 cannot escape outside the nozzle 7 as the pressure inside the chamber 5 is lowered, and the fluid stored in the fluid tank 40 is connected to the fluid transfer pipe 41. It is introduced into the chamber 5 through which the fluid is filled in the chamber 5.

On the other hand, when the current flowing in the other direction to the coil 11 is input, the length of the magnetostrictive member 9 is reduced, the push rod 15 is raised by the elastic restoring force of the elastic member 19 At the same time, the fluid is refilled into the chamber 5 and the fluid is not injected out of the nozzle 7.

Accordingly, the magnetostrictive inkjet head according to the present invention may adjust the amount of fluid that is pumped out of the nozzle 7 by varying the strength and direction of the current input to the coil 11, the external fluid tank 40 The fluid stored in the chamber 5 may be introduced into the chamber 5.

In addition, the use of the magnetostrictive member 9 as a power source for lowering the push rod 15 has the advantage of not applying high voltage or high heat to the fluid introduced into the chamber 5.

In addition, the magnetostrictive member 9 can exert a higher driving force than the piezoelectric element, so that the magnetostrictive member 9 does not have to be particularly concerned with the hole of the nozzle 7 from which the fluid is spouted.

3. Housing 5. Chamber
7. Nozzle 9. Magnetostrictive member
11. Coil 13. Permanent Magnet
15. Push Rod 17. Push Rod Head
19. Elastic member 21. Yoke
23. Flux pass section 24. Hook
25. Head gasket 26. Through hole
27. Upper connector housing 28. Hanging jaw
29. Upper insertion hole 30. Guide tube
31. Lower insertion hole 33. Lower connector housing
35. Nozzle gasket 37. Pipe insertion hole
39. Fitting connector 40. Fluid tank
41. Fluid delivery line 43. Tubing gasket

Claims

A housing 3;
A chamber 5 installed at a lower portion of the housing 3 to temporarily store fluid flowing from the outside and having an upper end opened;
A nozzle (7) connected at the upper end to the chamber (5) and having a lower end exposed outside the housing (3) to spray the fluid filled in the chamber (5) in the direction of the injection member (6);
A magnetostrictive member 9 which is inserted into and fixed inside the housing 3 and whose length increases or decreases according to the strength of the surrounding magnetic field;
A coil 11 which is inserted and fixed inside the housing 3 and installed outside the circumference of the magnetostrictive member 9 and whose strength or direction of the magnetic field is changed in accordance with an electrical signal input from the outside;
A permanent magnet (13) interposed between the housing (3) and the coil (11) or between the coil (11) and the magnetostrictive member (9) to generate a fixed strength and a magnetic field in a fixed direction;
The lower surface is lowered when the length of the magnetically deformed member 9 is extended while the upper surface is in contact with the lower surface of the magnetostrictive member 9 and the lower surface extends in the direction of the chamber 5 while being inserted into the housing 3. Push rod 15;
Mounted on the bottom surface of the push rod 15 and inserted into the chamber 5 through the open top surface of the chamber 5 so that fluid filled in the chamber 5 does not flow into the housing 3. A push rod head 17 moving upward and downward along the push rod 15;
In the state inserted into the housing 3, the bottom surface is fixed to the inner lower portion of the housing 3 and the top surface is fixed to any part of the push rod 15 to always deform the push rod 15 at all times. It consists of an elastic member 19 which pushes up in the direction of the member 9,
When a current flowing in one direction is input to the coil 11, the length of the magnetostrictive member 9 is increased so that the push rod 15 descends, and then the fluid filled in the chamber 5 is push rod head. Pushed out by (17) and spouted out of the nozzle (7),
When a current flowing in the other direction flows into the coil 11, the length of the magnetostrictive member 9 is reduced so that the push rod 15 is raised by the elastic restoring force of the elastic member 19, and at the same time, A magnetostrictive inkjet head characterized in that the fluid is refilled into the chamber (5) and no fluid is ejected out of the nozzle (7).

The method of claim 1,
Between the magnetostrictive member 9 and the coil 11, the shape of the coil 11 is preserved as it is, and a magnetic field generated from the coil 11 and the permanent magnet 13 is formed inside the housing 3. It is equipped with a yoke (21) to evenly herpes and define the path of movement of the magnetic field,
Flux pass portions 23 made of a magnetic material so that the magnetic field generated from the coil 11 or the permanent magnet 13 flows through the upper portion of the coil 11 or the lower portion of the coil 11 at upper and lower portions of the coil 11. Magnetostrictive inkjet head, characterized in that is installed.

The method of claim 2,
The side of the push rod 15 is provided with a catching hook 24 extending in the outward direction of the push rod 15,
The upper end of the elastic member 19 is in contact with the bottom surface of the locking hook 24 to push the locking hook 24 in the direction of the positive pass portion 23 located below the coil 11,
The inside of the housing 3 located above the chamber 5 is provided with a locking jaw 28 that can support the lower end of the elastic member 19,
The upper surface of the catching hook 24 is in contact with the positive pass portion 23 located under the coil 11 when the catching hook 24 is pushed up by the elastic member 19 to the magnetostrictive member 9. Magnetostrictive inkjet head, characterized in that.

The method of claim 1,
Magnetically deformable inkjet head, characterized in that the head gasket (25) is installed on the side circumferential surface of the push rod head (17) to prevent fluid filled in the chamber (5) from leaking into the interior of the housing (3).

The method of claim 1,
The lower part of the housing 3 is provided with a through hole 26 connected to the inside of the housing 3,
An upper connector housing 27 is mounted in the through hole 26 provided in the housing 3.
The upper insertion hole 29 is inserted into the upper connector housing 27 so that the upper surface of the upper connector housing 27 facing the inside of the housing 3 is moved in the vertical direction while the push rod head 17 is fitted. The inner side of the upper connector housing 27 in the upper surface of the
A chamber 5 in which a fluid is stored is installed inside the upper insertion hole 29.
The upper connector housing 27 is provided with a lower insertion hole 31 which is dug in the inward direction of the upper connector housing 27 from the bottom surface of the upper connector housing 27 and communicates with the chamber 5.
The lower connector hole 33 is installed in the lower insertion hole 31,
The lower connector housing 33 penetrates the nozzle 7 communicating with the chamber 5 so that the fluid filled in the chamber 5 is discharged out of the lower connector housing 33 through the nozzle 7,
A magnetostrictive inkjet head, characterized in that a nozzle gasket (35) is mounted between the chamber (5) and the nozzle (7) to prevent fluid from leaking between the chamber (5) and the nozzle (7).

6. The method of claim 5,
The upper connector housing 27 is connected to the chamber 5 via the circumferential surface of the upper connector housing 27 and the inner and upper insertion holes 29 of the upper connector housing 27 outside the upper connector housing 27. Equipped with a tube insertion hole 37,
In the tube insertion hole 37, a fitting connector 39 is provided to facilitate coupling of the chamber 5 and the fluid transfer tube 41 and to prevent fluid from leaking from the fluid transfer tube 41 or the chamber 5. Mounted,
The fitting connector 39 is equipped with a fluid transfer pipe 41 for moving the fluid stored in the external fluid tank 40 to the chamber 5,
Magnetic deformation, characterized in that the tubing gasket 43 is mounted to the fluid transfer pipe 41 and the chamber 5 is connected so that the fluid does not leak from the connection portion of the fluid transfer pipe 41 and the chamber 5 Inkjet head.