JP7098966B2 - Liquid discharge head, liquid discharge unit, liquid discharge device - Google Patents

Description

The present invention relates to a liquid discharge head, a liquid discharge unit, and a device for discharging a liquid.

As a liquid discharge head that discharges liquid, there is one provided with a nozzle cover member that covers the peripheral edge of the nozzle surface on which the nozzle is formed.

Conventionally, a nozzle cover that covers the peripheral edge of the nozzle surface and the outer peripheral side surface of the nozzle plate is provided, and the nozzle cover and the peripheral edge of the nozzle surface are arranged apart from each other, and the entire surface of the nozzle cover is treated with water repellent. It is known (Patent Document 1).

Japanese Unexamined Patent Publication No. 2009-220421

By the way, when fixing the cover member to the outer surface of the head, an adhesive or a filler is used. In this case, the liquid wiped from the nozzle surface comes into contact with the adhesive or the filler to cause elution, which may cause interface peeling between the adhesive and the cover member or the like. Further, as disclosed in Patent Document 1, when the entire surface of the cover member is subjected to a water repellent treatment, there is also a problem that peeling is more likely to occur.

The present invention has been made in view of the above problems, and an object of the present invention is to stably hold a cover member.

In order to solve the above problems, the liquid discharge head according to claim 1 of the present invention is
A nozzle plate having a nozzle surface on which a nozzle for discharging a liquid is formed,
A cover member that covers the peripheral edge of the nozzle surface and
A cover adhesive surface to which the cover member is adhered is provided.
The cover adhesive surface is arranged above the nozzle surface in the direction of gravity.
The cover member and the cover adhesive surface are adhered in the direction of gravity.
There is a gap between the cover member and the outer surface of the nozzle plate in the in-plane direction.
It was configured.

According to the present invention, the cover member can be stably held.

It is sectional drawing explanatory drawing of the liquid discharge head which concerns on 1st Embodiment of this invention. It is a plane explanatory view of the head. FIG. 3 is an enlarged explanatory view of a main part of FIG. 1 for explaining a holding structure of a cover member in the head. It is sectional drawing explanatory drawing of the nozzle plate and the cover member part of the comparative example 1. FIG. It is a plane explanatory view of the main part of an example of the apparatus which discharges a liquid which concerns on this invention. It is explanatory drawing of the main part side surface of the apparatus. It is a plane explanatory view of the main part of another example of the liquid discharge unit which concerns on this invention. It is a front explanatory view of still another example of the liquid discharge unit which concerns on this invention.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. The first embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a cross-sectional explanatory view of the liquid discharge head according to the embodiment, and FIG. 2 is a plan view of the head.

The liquid discharge head 100 has a nozzle plate 1, a flow path plate 2, and a diaphragm member 3 laminated and joined. Further, it includes a piezoelectric actuator 11 that displaces the vibration region (vibration plate) 30 of the diaphragm member 3, a frame member 20, and a cover member 50.

The nozzle plate 1 has a plurality of nozzles 4 for discharging a liquid. A liquid repellent film 40 is formed on the surface (liquid discharge surface side) of the nozzle plate 1. The peripheral edge of the nozzle surface (surface of the liquid repellent film 40) 1a of the nozzle plate 1 is covered with the cover member 50.

The flow path plate 2 forms an individual liquid chamber 6 that communicates with the nozzle 4. The diaphragm member 3 has a deformable vibration region 30 that forms the wall surface of the individual liquid chamber 6 of the flow path plate 2. Then, on the side of the diaphragm member 3 opposite to the individual liquid chamber 6, a piezoelectric actuator 11 including an electromechanical conversion element as a driving means (actuator means, pressure generating means) for deforming the vibration region 30 of the diaphragm member 3 is provided. It is arranged.

In this piezoelectric actuator 11, the piezoelectric member joined on the base member 13 is grooved by half-cut dying to form a required number of columnar piezoelectric elements 12 in a comb-teeth shape at predetermined intervals in the nozzle arrangement direction. ing. The piezoelectric element 12 is joined to the vibration region (diaphragm) 30.

In the liquid discharge head 100, for example, by lowering the voltage applied to the piezoelectric element 12 from the reference potential (intermediate potential), the piezoelectric element 12 contracts, the vibration region 30 of the vibrating plate member 3 is pulled, and the individual liquid chamber 6 As the volume expands, the liquid flows into the individual liquid chamber 6 from the common liquid chamber provided in the frame member 20.

After that, the voltage applied to the piezoelectric element 12 is increased to extend the piezoelectric element 12 in the stacking direction, and the vibration region 30 of the vibrating plate member 3 is deformed in the direction toward the nozzle 4 to contract the volume of the individual liquid chamber 6. As a result, the liquid in the individual liquid chamber 6 is pressurized, and the liquid is discharged from the nozzle 4.

The method of driving the head is not limited to the above example (pull-push), and pulling or pushing may be performed depending on the driving waveform.

Next, FIG. 3 also describes the holding structure of the cover member 50 in the liquid discharge head 100. FIG. 3 is an enlarged explanatory view of a main part of FIG. 1 for the same explanation.

A cover holding portion 60 for holding the cover member 50 is joined and fixed to the outer peripheral portion of the frame member 20 with an adhesive 70. The adhesive surface 52 of the cover member 50 and the cover adhesive surface 62 of the cover holding portion 60 are joined and fixed with an adhesive 71.

Here, the cover adhesive surface 62 of the cover holding portion 60 to which the cover member 50 is adhered is arranged above the nozzle surface (surface of the liquid repellent film 40) 1a in the direction of gravity.

The cover member 50 has a facing portion 51 that faces the peripheral edge portion of the nozzle surface 1a of the nozzle plate 1 with a gap g placed therein and covers the peripheral edge portion of the gap. The gap g is preferably in the range of 1 μm to 50 μm. Within this range, the waste liquid 81 (see FIG. 3) on the nozzle surface 1a can be easily wiped off.

Then, a liquid-repellent treatment for forming a liquid-repellent film 40 is applied to the outer surface including the surface of the facing portion 51 of the cover member 50.

On the other hand, the surface 53 facing the outer surface 1b of the nozzle plate 1 of the cover member 50 and the adhesive surface 52 adhesively bonded to the cover adhesive surface 62 of the cover holding portion 60 are subjected to a liquid repellent treatment such as forming a liquid repellent film 40. Not given. That is, in the cover member 50, the liquid repellency of the adhesive surface 52, which is the portion that adheres to the cover adhesive surface 62, is lower than the liquid repellency of the portion that does not contact the cover adhesive surface 62.

As described above, the adhesive surface 52 of the cover member 50 to be adhesively bonded to the cover adhesive surface 62 of the cover holding portion 60 is not subjected to the liquid repellent treatment, and the liquid repellent property is lowered, so that the cover holding portion 60 is peeled off. The cover member 50 can be stably joined without causing such a problem.

Next, the operation on this liquid discharge head will be described.

As shown in FIG. 3, by wiping the nozzle surface 1a with the wiping member 80, the waste liquid 81 remaining on the nozzle surface 1a is scraped up to the peripheral edge portion of the nozzle surface 1a. The scraped liquid 81 is about to be pushed into the gap g between the facing portion 51 of the cover member 50 and the nozzle surface 1a.

At this time, since the liquid repellent film 40 is also formed on the surface of the facing portion 51 of the cover member 50, the waste liquid 81 is repelled in the state of drops and cannot enter the gap g. Therefore, the waste liquid 81 is removed from the nozzle surface 4a while still adhering to the wiping member 80.

Here, the cover adhesive surface 62 of the cover holding portion 60 for adhering the cover member 50 is arranged above the nozzle surface 1a in the direction of gravity. Therefore, as shown in FIG. 3, even if the waste liquid 81a enters between the outer surface 1b of the nozzle plate 1 and the inner peripheral surface 53 of the cover member 50, gravity causes the cover member 50 and the cover adhesive surface 62 to enter. It does not reach the adhesive 71 that joins with.

As a result, it is possible to prevent the adhesive 71 adhering the cover member 50 and the cover adhesive surface 62 from being melted by the waste liquid 81 and causing interfacial peeling between the adhesive 71 and the adhesive surfaces 52 and 62. , The cover member 50 can be stably held.

Further, the adhesive surface 52 to be joined by the adhesive 71 of the cover member 50 is not subjected to a liquid repellent treatment such as forming a liquid repellent film 40. As a result, the peelability (easiness of peeling) of the cover due to the liquid-repellent film can be reduced.

Further, the adhesive surface 52 of the cover member 50 is provided so as to be separated from the end portion of the nozzle surface 1a in a direction orthogonal to the liquid discharge direction (left-right direction in FIG. 3).

As a result, even if the waste liquid 81 invades between the outer surface 1b of the nozzle plate 1 and the inner peripheral surface 53 of the cover member 50, it is possible to more reliably prevent the liquid from reaching the adhesive 71.

Here, Comparative Example 1 will be described with reference to FIG. FIG. 4 is a cross-sectional explanatory view of the nozzle plate and the cover member portion of Comparative Example 1.

In Comparative Example 1, the cover member 50 is fixed to the peripheral edge of the nozzle plate 1 with the filler 72.

In this configuration, the waste liquid 81 comes into contact with the filler 72, and if the liquid resistance of the filler 72 is low, inconveniences such as peeling of the cover member 50 will occur.

In the above embodiment, the cover holding portion 60 is fixed to the outer peripheral surface of the frame member 20, but the frame member 20 can also serve as the cover holding portion. At least, the cover adhesive surface of the cover holding portion may be arranged above the nozzle surface in the direction of gravity.

Further, the liquid discharge head may be an individual liquid chamber circulation type liquid discharge head.

Next, an example of the device for discharging the liquid according to the present invention will be described with reference to FIGS. 5 and 6. FIG. 5 is an explanatory plan view of a main part of the device, and FIG. 6 is an explanatory view of a side surface of the main part of the device.

This device is a serial type device, and the carriage 403 is reciprocated in the main scanning direction by the main scanning moving mechanism 493. The main scanning movement mechanism 493 includes a guide member 401, a main scanning motor 405, a timing belt 408, and the like. The guide member 401 is bridged over the left and right side plates 491A and 491B to movably hold the carriage 403. Then, the carriage 403 is reciprocated in the main scanning direction by the main scanning motor 405 via the timing belt 408 bridged between the drive pulley 406 and the driven pulley 407.

The carriage 403 is equipped with a liquid discharge unit 440 in which the liquid discharge head 404 and the head tank 441 according to the present invention are integrated. The liquid discharge head 404 of the liquid discharge unit 440 discharges, for example, liquids of each color of yellow (Y), cyan (C), magenta (M), and black (K). Further, the liquid discharge head 404 is mounted by arranging a nozzle row composed of a plurality of nozzles in a sub-scanning direction orthogonal to the main scanning direction and facing the discharge direction downward.

The liquid stored in the liquid cartridge 450 is supplied to the head tank 441 by the supply mechanism 494 for supplying the liquid stored outside the liquid discharge head 404 to the liquid discharge head 404.

The supply mechanism 494 includes a cartridge holder 451 which is a filling part for mounting the liquid cartridge 450, a tube 456, a liquid feeding unit 452 including a liquid feeding pump, and the like. The liquid cartridge 450 is detachably attached to the cartridge holder 451. Liquid is delivered from the liquid cartridge 450 to the head tank 441 by the liquid feeding unit 452 via the tube 456.

This device includes a transport mechanism 495 for transporting the paper 410. The transport mechanism 495 includes a transport belt 412, which is a transport means, and a sub-scanning motor 416 for driving the transport belt 412.

The transport belt 412 attracts the paper 410 and transports it at a position facing the liquid discharge head 404. The transport belt 412 is an endless belt, and is hung between the transport roller 413 and the tension roller 414. Adsorption can be performed by electrostatic adsorption, air suction, or the like.

Then, the transport belt 412 orbits in the sub-scanning direction by rotationally driving the transport roller 413 via the timing belt 417 and the timing pulley 418 by the sub-scanning motor 416.

Further, on one side of the carriage 403 in the main scanning direction, a maintenance / recovery mechanism 420 for maintaining / recovering the liquid discharge head 404 is arranged on the side of the transport belt 412.

The maintenance / recovery mechanism 420 is composed of, for example, a cap member 421 that caps the nozzle surface (the surface on which the nozzle is formed) of the liquid discharge head 404, a wiper member 422 that wipes the nozzle surface, and the like.

The main scanning movement mechanism 493, the supply mechanism 494, the maintenance / recovery mechanism 420, and the transport mechanism 495 are attached to a housing including the side plates 491A and 491B and the back plate 491C.

In this apparatus configured in this way, the paper 410 is fed onto the transport belt 412 and sucked, and the paper 410 is conveyed in the sub-scanning direction by the circumferential movement of the conveyor belt 412.

Therefore, by driving the liquid ejection head 404 in response to the image signal while moving the carriage 403 in the main scanning direction, the liquid is ejected onto the stopped paper 410 to form an image.

As described above, since this device includes the liquid discharge head according to the present invention, it is possible to stably form a high-quality image.

Next, another example of the liquid discharge unit according to the present invention will be described with reference to FIG. 7. FIG. 70 is an explanatory plan view of a main part of the unit.

This liquid discharge unit includes a housing portion composed of side plates 491A, 491B and a back plate 491C, a main scanning movement mechanism 493, a carriage 403, and a liquid among the members constituting the device for discharging the liquid. It is composed of a discharge head 404.

It should be noted that a liquid discharge unit may be configured in which at least one of the above-mentioned maintenance / recovery mechanism 420 and the supply mechanism 494 is further attached to, for example, the side plate 491B of the liquid discharge unit.

Next, still another example of the liquid discharge unit according to the present invention will be described with reference to FIG. FIG. 8 is a front explanatory view of the unit.

This liquid discharge unit includes a liquid discharge head 404 to which the flow path component 444 is attached, and a tube 456 connected to the flow path component 444.

The flow path component 444 is arranged inside the cover 442. A head tank 441 may be included instead of the flow path component 444. Further, a connector 443 that electrically connects to the liquid discharge head 404 is provided on the upper part of the flow path component 444.

In the present application, the liquid to be discharged may have a viscosity and surface tension that can be discharged from the head, and is not particularly limited, but the viscosity becomes 30 mPa · s or less at room temperature, under normal pressure, or by heating or cooling. It is preferable that it is a thing. More specifically, solvents such as water and organic solvents, colorants such as dyes and pigments, polymerizable compounds, resins, functionalizing materials such as surfactants, biocompatible materials such as DNA, amino acids and proteins, and calcium. , Solvents, suspensions, emulsions, etc. containing edible materials such as natural pigments, such as inks for inkjets, surface treatment liquids, components of electronic and light emitting elements, and formation of electronic circuit resist patterns. It can be used in applications such as liquids and material liquids for three-dimensional modeling.

Piezoelectric actuators (laminated piezoelectric elements and thin-film piezoelectric elements), thermal actuators that use electric heat conversion elements such as heat-generating resistors, and electrostatic actuators that consist of a vibrating plate and counter electrodes are used as energy sources for discharging liquid. Includes what to do.

The "liquid discharge unit" is a liquid discharge head integrated with functional parts and a mechanism, and includes a collection of parts related to liquid discharge. For example, the "liquid discharge unit" includes a head tank, a carriage, a supply mechanism, a maintenance / recovery mechanism, a main scanning movement mechanism in which at least one of the configurations is combined with a liquid discharge head, and the like.

Here, the term "integration" means, for example, a liquid discharge head and a functional component, a mechanism in which the mechanism is fixed to each other by fastening, bonding, engagement, etc., or one in which one is movably held with respect to the other. include. Further, the liquid discharge head, the functional component, and the mechanism may be configured to be detachable from each other.

For example, as a liquid discharge unit, there is a unit in which a liquid discharge head and a head tank are integrated. In some cases, the liquid discharge head and the head tank are integrated by being connected to each other by a tube or the like. Here, a unit including a filter can be added between the head tank of these liquid discharge units and the liquid discharge head.

Further, as a liquid discharge unit, there is a unit in which a liquid discharge head and a carriage are integrated.

Further, there is a liquid discharge unit in which the liquid discharge head and the scanning movement mechanism are integrated by holding the liquid discharge head movably by a guide member constituting a part of the scanning movement mechanism. In some cases, the liquid discharge head, the carriage, and the main scanning movement mechanism are integrated.

Further, as a liquid discharge unit, there is a carriage to which a liquid discharge head is attached, in which a cap member which is a part of the maintenance / recovery mechanism is fixed, and the liquid discharge head, the carriage, and the maintenance / recovery mechanism are integrated. ..

Further, as a liquid discharge unit, there is a liquid discharge unit in which a tube is connected to a head tank or a liquid discharge head to which a flow path component is attached, and the liquid discharge head and a supply mechanism are integrated. The liquid of the liquid storage source is supplied to the liquid discharge head through this tube.

The main scanning movement mechanism shall include a single guide member. Further, the supply mechanism includes a single tube and a single loading unit.

The "device for discharging a liquid" includes a device provided with a liquid discharge head or a liquid discharge unit and driving the liquid discharge head to discharge the liquid. The device for discharging a liquid includes not only a device capable of discharging a liquid to a device to which the liquid can adhere, but also a device for discharging the liquid into the air or into the liquid.

The "device for discharging the liquid" may include means for feeding, transporting, and discharging paper to which the liquid can adhere, as well as a pretreatment device, a posttreatment device, and the like.

For example, as a "device that ejects a liquid", an image forming device that is a device that ejects ink to form an image on paper, and a three-dimensional model (three-dimensional model) are formed in layers in order to form a three-dimensional model. There is a three-dimensional modeling device (three-dimensional modeling device) that discharges the modeling liquid into the powder layer.

Further, the "device for discharging liquid" is not limited to a device in which a significant image such as characters and figures is visualized by the discharged liquid. For example, those that form patterns that have no meaning in themselves and those that form a three-dimensional image are also included.

The above-mentioned "thing to which a liquid can adhere" means a material to which a liquid can adhere at least temporarily, such as a material to which the liquid adheres and adheres, and a material to which the liquid adheres and permeates. Specific examples include paper, recording paper, recording paper, film, recorded media such as cloth, electronic substrates, electronic components such as piezoelectric elements, powder layers (powder layers), organ models, and media such as inspection cells. Yes, and includes everything to which the liquid adheres, unless otherwise specified.

The material of the above-mentioned "material to which liquid can adhere" may be paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, ceramics or the like as long as the liquid can adhere even temporarily.

Further, the "device for discharging the liquid" includes, but is not limited to, a device in which the liquid discharge head and the device to which the liquid can adhere move relatively. Specific examples include a serial type device that moves the liquid discharge head, a line type device that does not move the liquid discharge head, and the like.

In addition, as a "device for ejecting a liquid", a treatment liquid coating device for ejecting a treatment liquid to the paper in order to apply the treatment liquid to the surface of the paper for the purpose of modifying the surface of the paper, etc. There is an injection granulator that granulates fine particles of a raw material by injecting a composition liquid in which a raw material is dispersed in a solution through a nozzle.

In addition, in the term of this application, image formation, recording, printing, printing, printing, modeling, etc. are all synonymous.

1 Nozzle plate 2 Flow plate 3 Diaphragm member 4 Nozzle 6 Individual liquid chamber 40 Liquid repellent film 50 Cover member 60 Cover holding part 61 Cover adhesive surface 71 Adhesive 100 Liquid discharge head 403 Carriage 404 Liquid discharge head 440 Liquid discharge unit

Claims (11)

A nozzle plate having a nozzle surface on which a nozzle for discharging a liquid is formed,
A cover member that covers the peripheral edge of the nozzle surface and
A cover adhesive surface to which the cover member is adhered is provided.
The cover adhesive surface is arranged above the nozzle surface in the direction of gravity.
The cover member and the cover adhesive surface are adhered in the direction of gravity.
There is a gap between the cover member and the outer surface of the nozzle plate in the in-plane direction.
A liquid discharge head characterized by that. A nozzle plate having a nozzle surface on which a nozzle for discharging a liquid is formed,
A cover member that covers the peripheral edge of the nozzle surface and
A cover adhesive surface to which the cover member is adhered is provided.
The cover adhesive surface is arranged above the nozzle surface in the direction of gravity.
The cover member and the cover adhesive surface are adhered in the direction of gravity.
A liquid discharge head characterized in that a liquid repellent treatment is applied to the facing regions of the nozzle surface and the cover member. The liquid discharge head according to claim 1 or 2 , wherein the cover member has a liquid repellency of a portion that adheres to the cover adhesive surface lower than a liquid repellency of a portion that does not contact the cover adhesive surface. .. The liquid discharge head according to claim 3 , wherein the portion of the cover member to be adhered to the cover adhesive surface is not subjected to a liquid repellent treatment. The liquid discharge head according to any one of claims 1 to 4 , wherein the cover member and the cover adhesive surface are adhered to each other on the side of the outer surface in the in-plane direction of the nozzle plate. The liquid discharge head according to claim 2, wherein there is a gap between the cover member and the outer surface of the nozzle plate in the in-plane direction. The liquid discharge head according to any one of claims 1 to 6 , further comprising a cover holding portion having the cover adhesive surface. The liquid discharge head according to claim 1, wherein the nozzle surface and the respective facing regions of the cover member are subjected to a liquid repellent treatment. A liquid discharge unit comprising the liquid discharge head according to any one of claims 1 to 8 . A head tank that stores the liquid to be supplied to the liquid discharge head, a carriage on which the liquid discharge head is mounted, a supply mechanism that supplies the liquid to the liquid discharge head, a maintenance / recovery mechanism that maintains and recovers the liquid discharge head, and the liquid. The liquid discharge unit according to claim 9 , wherein at least one of the main scanning moving mechanisms for moving the discharge head in the main scanning direction is integrated with the liquid discharge head. A device for discharging a liquid, comprising the liquid discharge head according to any one of claims 1 to 8 or the liquid discharge unit according to claim 9 or 10 .

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