JP6897195B2 - 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, among the liquids supplied from the common liquid chamber on the supply side to the individual liquid chambers, the liquid that has not been discharged is returned from the discharge flow path to the common liquid chamber on the discharge side, and the liquid is circulated. , A circulation type head (flow-through head) for improving the discharge property of air bubbles mixed in the individual liquid chamber and suppressing the change in the characteristics of the liquid is known.

Conventionally, it is known that a supply side damper is installed in a flow path on the supply side connected to each head module (liquid discharge head), and a discharge side damper is installed in the flow path on the discharge side (patented). Document 1).

Japanese Unexamined Patent Publication No. 2016-187892

By the way, in the non-circulation type liquid discharge head, in order to reduce the variation in discharge characteristics due to the pressure wave generated by the discharge of the liquid propagating to the common liquid chamber on the supply side and repropagating to the individual liquid chamber side. A damper member for attenuating the pressure wave is arranged in the common liquid chamber on the supply side.

On the other hand, in the circulation type head, since the discharge side common liquid chamber communicates with the individual liquid chamber through the discharge flow path, the pressure wave from the individual liquid chamber propagates to the discharge side common liquid chamber through the discharge flow path. There is a problem that it propagates back to the discharge flow path again and affects the discharge characteristics.

The present invention has been made in view of the above problems, and an object of the present invention is to reduce variations in discharge characteristics.

In order to solve the above problems, the liquid discharge head according to the present invention is
Multiple nozzles that discharge liquid and
A plurality of individual liquid chambers communicating with the plurality of nozzles, and
A common liquid chamber on the supply side leading to the plurality of individual liquid chambers,
A plurality of discharge channels communicating with each of the plurality of individual liquid chambers,
A common liquid chamber on the discharge side leading to the plurality of discharge channels ,
A discharge-side damper forming the wall surface of the discharge-side common liquid chamber,
A supply-side damper that forms the wall surface of the supply-side common liquid chamber is provided.
The discharge side damper and the supply side damper are integral members.
The supply-side common liquid chamber and the discharge-side common liquid chamber have a portion that overlaps when one is projected onto the other in the direction perpendicular to the nozzle surface.
At least one of the supply side damper and the discharge side damper is arranged in the overlapping portion .

According to the present invention, it is possible to reduce variations in discharge characteristics.

It is an external perspective explanatory view of the liquid discharge head which concerns on 1st Embodiment of this invention. It is sectional drawing in the direction orthogonal to the nozzle arrangement direction of the head. It is a plane explanatory view which saw each member of the head from the nozzle side. It is a plane explanatory view which saw each member of the head from the side opposite to a nozzle. It is an exploded perspective explanatory view of the head. It is sectional drawing in the direction orthogonal to the nozzle arrangement direction of the liquid discharge head which concerns on 2nd Embodiment of this invention. It is a plane explanatory view which saw each member of the head from the nozzle side. It is a plane explanatory view which saw each member of the head from the side opposite to a nozzle. It is sectional drawing in the direction orthogonal to the nozzle arrangement direction of the liquid discharge head which concerns on 3rd Embodiment of this invention. It is sectional drawing in the direction orthogonal to the nozzle arrangement direction of the liquid discharge head which concerns on 4th Embodiment of this invention. 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 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. It is a schematic explanatory drawing of another example of the apparatus which discharges a liquid which concerns on this invention. It is a plane explanatory view of the head unit of this apparatus. It is a block explanatory drawing which provides the explanation of an example of the liquid circulation system in this apparatus.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. The liquid discharge head according to the first embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is an external perspective explanatory view of the liquid discharge head, and FIG. 2 is a cross-sectional explanatory view in a direction orthogonal to the nozzle arrangement direction of the head.

In this liquid discharge head, a nozzle plate 1, a flow path plate 2, and a diaphragm member 3 as a wall surface member are laminated and joined. A piezoelectric actuator 11 that displaces the vibration region (vibration plate) 30 of the diaphragm member 3, a common liquid chamber member 20 that also serves as a frame member of the head, and a cover 29 are provided.

The nozzle plate 1 has a plurality of nozzles 4 for discharging a liquid.

The flow path plate 2 is a supply that leads to an individual liquid chamber 6 that communicates with the nozzle 4 via the nozzle communication passage 5, a supply-side fluid resistance portion 7 that constitutes a supply flow path that leads to the individual liquid chamber 6, and a supply-side fluid resistance portion 7. The side introduction portion 8 is formed. The supply-side introduction unit 8 may be configured to communicate with one or a plurality of supply-side fluid resistance units 7.

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. Here, the diaphragm member 3 has a two-layer structure (not limited), and is formed of a first layer for forming a thin-walled portion from the flow path plate 2 side and a second layer for forming a thick-walled portion. A deformable vibration region 30 is formed in a portion corresponding to the individual liquid chamber 6.

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.

The piezoelectric actuator 11 is grooved in the piezoelectric member 12 joined on the base member 13 by half-cut dicing, and a required number of columnar piezoelectric elements 12A and 12B are formed into comb teeth at predetermined intervals in the nozzle arrangement direction. Is forming.

Then, the piezoelectric element 12A is joined to the convex portion 30a which is an island-shaped thick portion formed in the vibration region (vibration plate) 30 of the diaphragm member 3. Further, the piezoelectric element 12B is joined to the thick portion of the diaphragm member 3 between the individual liquid chambers 6.

The piezoelectric member 12 is formed by alternately stacking piezoelectric layers and internal electrodes. The internal electrodes are drawn out to their end faces to provide external electrodes, and the flexible wiring member 15 is connected to the external electrodes.

The common liquid chamber member 20 forms a supply side common liquid chamber 10 and a discharge side common liquid chamber 50. The supply-side common liquid chamber 10 is connected to the supply port 41, and the discharge-side common liquid chamber 50 is connected to the discharge port 42 (FIG. 1).

The supply-side common liquid chamber 10 communicates with the supply-side introduction unit 8 via the supply-side filter 9. The supply side filter 9 is formed by the first layer of the diaphragm member 3.

Further, the flow path plate 2 forms a discharge-side fluid resistance portion 57 and a discharge-side lead-out portion 58 that form a discharge flow path that leads to each individual liquid chamber 6 via the nozzle communication passage 5. The discharge-side lead-out unit 58 may be configured to communicate with one or a plurality of discharge-side fluid resistance units 57.

The discharge side lead-out unit 58 communicates with the discharge side common liquid chamber 50 via the discharge side filter 59. The discharge side filter 59 is formed by the first layer of the diaphragm member 3.

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

After that, the voltage applied to the piezoelectric element 12A is increased to extend the piezoelectric element 12A 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.

Further, the liquid that is not discharged from the nozzle 4 passes through the nozzle 4 and is discharged from the discharge side fluid resistance unit 57 through the discharge side lead-out unit 58 to the discharge side common liquid chamber 50, and is discharged from the discharge side common liquid chamber 50 to an external circulation path. It is supplied again to the common liquid chamber 10 on the supply side through. Further, even when the liquid is not discharged, the liquid flows from the supply side common liquid chamber 10 to the discharge side common liquid chamber 50, and is further supplied to the supply side common liquid chamber 10 through an external circulation path.

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

Next, the structure of the common liquid chamber in the liquid discharge head according to the present embodiment will be described with reference to FIG.

The common liquid chamber member 20 is configured by sequentially laminating the first member 21, the second member 22, the damper chamber member 83, the damper member 81, the damper chamber member 82, and the third member 23 from the diaphragm member 3 side. The supply side common liquid chamber 10 and the discharge side common liquid chamber 50 are formed.

The supply-side common liquid chamber 10 is a portion that is aligned with the discharge-side common liquid chamber 50 in a direction orthogonal to the nozzle arrangement direction, a downstream-side common liquid chamber portion 10A, and a portion that is not aligned with the discharge-side common liquid chamber 50. Includes side common liquid chamber portion 10B.

The discharge-side common liquid chamber 50 and the supply-side common liquid chamber 10 have overlapping portions when one is projected onto the other in the direction perpendicular to the nozzle surface. Here, a part 10b of the upstream side common liquid chamber portion 10B and a part 10b of the discharge side common liquid chamber 50 are overlapping portions when projected (hereinafter, the part 10b is referred to as “overlapping portion 10b”).

The damper member 81 forms a discharge side damper 85 that forms the wall surface of the discharge side common liquid chamber 50 and a supply side damper 86 that forms the wall surface of the supply side common liquid chamber 10.

The damper chamber member 82 forms a damper chamber (gas chamber) 87 on the side opposite to the discharge side common liquid chamber 50 with the discharge side damper 85 interposed therebetween. The damper chamber member 83 forms a damper chamber (gas chamber) 88 on the side opposite to the upstream side common liquid chamber portion 10B of the supply side common liquid chamber 10 with the supply side damper 86 interposed therebetween.

As described above, the discharge side damper 85 that forms the wall surface of the discharge side common liquid chamber 50 is provided. As a result, when the pressure wave accompanying the liquid discharge propagates to the discharge side common liquid chamber 50 through the discharge side fluid resistance unit 57 and the discharge side lead-out unit 58, the pressure wave can be attenuated or absorbed by the discharge side damper 85. , Repropagation to the nozzle 4 side can be prevented. Therefore, it is possible to reduce the variation in discharge characteristics due to the repropagation of the pressure wave from the discharge side common liquid chamber 50 to the nozzle 4 side.

Further, a supply side damper 86 forming a wall surface of the supply side common liquid chamber 10 is provided. As a result, when the pressure wave accompanying the liquid discharge propagates to the supply side common liquid chamber 10 through the supply side fluid resistance unit 7 and the supply side introduction unit 8, the pressure wave can be attenuated or absorbed by the supply side damper 86. , Repropagation to the individual liquid chamber 6 side can be prevented. Therefore, it is possible to reduce the variation in discharge characteristics due to the repropagation of the pressure wave from the common liquid chamber 10 on the supply side to the individual liquid chamber 6 side.

Further, in the present embodiment, since the discharge side damper 85 and the supply side damper 86 are formed of the same damper member 81, the number of parts can be reduced and the configuration becomes simple.

Further, in the present embodiment, the supply side damper 86 is the wall surface of the upstream side common liquid chamber portion 10B in the supply side common liquid chamber 10, and the overlapping portion 10b whose projection position overlaps with the discharge side common liquid chamber 50. It is placed on the wall surface of.

As a result, the supply side damper 86 and the discharge side damper 85 can be provided without increasing the head size while securing the supply side common liquid chamber 10 and the discharge side common liquid chamber 50 having sufficient capacities.

Therefore, by attenuating the pressure wave on the discharge side and the supply side in the same manner, the supply side and the discharge side are reversed, that is, the supply side is used as the discharge side and the discharge side is used as the supply side. You can also do it.

Here, each part constituting the liquid discharge head of the present embodiment will be described with reference to FIGS. 3 to 5. FIG. 3 is a plan explanatory view of each member of the head viewed from the nozzle side, FIG. 4 is a plan explanatory view of each member of the head viewed from the side opposite to the nozzle, and FIG. 5 is an exploded perspective explanatory view of the head. ..

As shown in FIGS. 3A and 4A, a plurality of nozzles 4 are formed on the nozzle plate 1.

As shown in FIGS. 3 (b) to (e) and FIGS. 4 (b) to (e), the flow path plate 2 is composed of plate-shaped members 2A to 2D.

As shown in FIGS. 3 (c) and 4 (b), the plate-shaped member 2A of the flow path plate 2 includes a part of the nozzle communication passage 5, a discharge-side fluid resistance portion 57, and a discharge-side lead-out portion 58. A through groove portion (meaning a groove-shaped through hole) 57b is formed to form the portion.

Similarly, as shown in FIGS. 3 (c) and 4 (c), the plate-shaped member 2B is formed with a through hole 5c forming a part of the nozzle communication passage 5 and a part of the discharge side lead-out portion 58. A through groove portion 58c is formed.

Similarly, as shown in FIGS. 3D and 4D, the plate-shaped member 2C has a through hole 5d forming a part of the nozzle communication passage 5 and a through groove portion forming the supply side fluid resistance portion 7. 7d and a through groove portion 58d forming a part of the discharge side lead-out portion 58 are formed.

Similarly, in the plate-shaped member 2D, as shown in FIGS. 3 (e) and 4 (e), a through groove portion 6e forming the individual liquid chamber 6 and a through groove portion 8e forming the supply side introduction portion 8 are discharged. A through groove portion 58e forming a part of the side lead-out portion 58 is formed.

As shown in FIGS. 3 (f) and 4 (f), the diaphragm member 3 is formed with a supply side filter 9 and a discharge side filter 59.

As shown in FIGS. 3 (g) and 4 (g), the first member 21 constituting the common liquid chamber member 20 has a through groove portion 10 g forming a part of the common liquid chamber 10 on the supply side and a discharge side. A through groove portion 50 g forming a part of the common liquid chamber 50 is formed. Further, the first member 21 has a through hole 42g forming a part of the internal flow path of the discharge port 42 and a through groove portion forming a part of the actuator accommodating portion 24 (see FIG. 2) accommodating the piezoelectric actuator 11. 24 g is formed.

Similarly, as shown in FIGS. 3 (h) and 4 (h), the damper chamber member 83 has a through groove portion 10h forming a part of the supply-side common liquid chamber 10 and a part of the discharge-side common liquid chamber 50. A through groove portion 50h forming the damper chamber 88 and a recess 88h forming the damper chamber 88 are formed. Further, the damper chamber member 83 is formed with a through hole 42h forming a part of the internal flow path of the discharge port 42 and a through groove portion 24h forming a part of the actuator accommodating portion 24.

Similarly, as shown in FIGS. 3 (i) and 4 (i), the damper member 81 has a through groove portion 10i forming a part of the supply side common liquid chamber 10 and a part of the discharge side common liquid chamber 50. The through groove portion 50i to be formed, the discharge side damper 85, and the supply side damper 86 are formed. Further, the damper member 81 is formed with a through hole 42i forming a part of the internal flow path of the discharge port 42 and a through groove portion 24i forming a part of the actuator accommodating portion 24.

Similarly, as shown in FIGS. 3 (j) and 4 (j), the damper chamber member 82 has the through groove portions 10j1 and 10j2 forming a part of the supply-side common liquid chamber 10 and the discharge-side common liquid chamber 50. A through groove portion 50j forming a part thereof and a recess 87j forming the damper chamber 87 are formed. Further, the damper chamber member 82 is formed with a through hole 42j forming a part of the internal flow path of the discharge port 42 and a through groove portion 24j forming a part of the actuator accommodating portion 24.

Similarly, as shown in FIGS. 3 (k) and 4 (k), the second member 22 is formed with a through groove portion 10k that forms a part of the common liquid chamber 10 on the supply side. Further, the second member 22 has a through hole 41k forming a part of the internal flow path of the supply port 41, a through hole 42k forming a part of the internal flow path of the discharge port 42, and an actuator accommodating portion 24. A through groove portion 24k forming a part is formed.

Similarly, as shown in FIGS. 3 (l) and 4 (l), the third member 23 is formed with a through groove portion 24k forming a part of the actuator accommodating portion 24 and a part of the supply side common liquid chamber 10. A through groove portion 10k is formed, a through hole 41k forming a part of the internal flow path of the supply port 41, and a through hole 42k forming a part of the internal flow path of the discharge port 42 are formed.

Piezoelectric elements 12A and 12B are formed on the piezoelectric member 12 as shown in FIGS. 3 (m) and 4 (m).

Next, the liquid discharge head according to the second embodiment of the present invention will be described with reference to FIG. FIG. 6 is a cross-sectional explanatory view in a direction orthogonal to the nozzle arrangement direction of the head.

In the present embodiment, the supply side common liquid chamber 10, the supply side introduction unit 8, and the supply side fluid resistance unit 7 are arranged on one side of the nozzle 4 in a direction orthogonal to the nozzle arrangement direction. Liquid is supplied from the common liquid chamber 10 to the individual liquid chamber 6.

Here, the supply-side introduction unit 8 communicates with a plurality of supply-side fluid resistance units 7. As a result, even when the supply-side filter 9 is clogged with time, the liquid can be supplied by bypassing the clogged portion, so that an increase in pressure loss can be suppressed.

Further, in the direction orthogonal to the nozzle arrangement direction, the discharge side fluid resistance portion 57, the discharge side lead-out portion 58, and the discharge side common liquid chamber 50 are arranged on the other side with the nozzle 4 sandwiched, and the nozzle is discharged from the nozzle communication passage 5. The liquid is discharged to the side common liquid chamber 50.

Here, the discharge side lead-out unit 58 is composed of an individual lead-out unit 58A that communicates with each discharge-side fluid resistance unit 57, and one or a plurality of common lead-out units 58B that a plurality of individual lead-out units 58A communicate in common. There is. As a result, even when the discharge side filter 59 is clogged with time, the liquid can be discharged by bypassing the clogged portion, so that an increase in pressure loss can be suppressed.

Further, the supply side common liquid chamber 10 and the discharge side common liquid chamber 50 are formed of a common liquid chamber member 20, and a damper member 81 and a damper chamber member 84 are laminated on the common liquid chamber member 20. The damper member 81 forms a discharge side damper 85 that forms the wall surface of the discharge side common liquid chamber 50 and a supply side damper 86 that forms the wall surface of the supply side common liquid chamber 10. The damper chamber member 84 forms the damper chambers 87 and 88.

By arranging the supply side and the discharge side on opposite sides of the nozzle row as in the present embodiment, the compliance between the supply side and the discharge side can be easily made the same.

Further, since the flow path shape can be made substantially the same on the supply side and the discharge side and the pressure loss can be easily made the same, the supply side and the discharge side can be interchanged and used. As a result, when a plurality of liquid discharge heads of the present embodiment are arranged to form a long head, various methods can be used as the piping method when piping to the supply port and the discharge port.

Next, each part constituting the liquid discharge head of the present embodiment will be described with reference to FIGS. 7 and 8. FIG. 7 is a plan explanatory view of each member of the head viewed from the nozzle side, and FIG. 8 is a plan explanatory view of each member of the head viewed from the side opposite to the nozzle.

As shown in FIGS. 7A and 8A, a plurality of nozzles 4 are formed on the nozzle plate 1.

As shown in FIGS. 7 (b) to (d) and 4 (b) to (d), the flow path plate 2 is composed of plate-shaped members 2A to 2C.

As shown in FIGS. 7 (c) and 8 (b), the plate-shaped member 2A of the flow path plate 2 includes a part of the nozzle communication passage 5, a discharge side fluid resistance part 57, and a part of the individual lead-out part 58A. 57b is formed as a through groove portion (meaning a groove-shaped through hole).

Similarly, as shown in FIGS. 7 (c) and 8 (c), the plate-shaped member 2B has a through groove portion 7c forming the supply side fluid resistance portion 7 and a through hole forming a part of the nozzle communication passage 5. The 5c and the through groove portion 58c forming a part of the individual lead-out portion 58A are formed.

Similarly, in the plate-shaped member 2C, as shown in FIGS. 7 (d) and 8 (d), as shown in FIGS. 7 (d) and 8 (d), the through groove portion 6d forming the individual liquid chamber 6 is formed. A through groove portion 8d forming the supply side introduction portion 8 and a through groove portion 58d forming a part of the common lead-out portion 58B are formed.

As shown in FIGS. 7 (e) and 8 (e), the diaphragm member 3 is formed with a supply side filter 9 and a discharge side filter 59.

As shown in FIGS. 7 (f) and 8 (f), the common liquid chamber member 20 is formed with a through groove portion 10f forming a part of the supply side common liquid chamber 10 and a discharge side common liquid chamber 50. A through groove portion 50f is formed. Further, the common liquid chamber member 20 has a through hole 42f forming a part of the internal flow path of the discharge port 42, a through hole 41f forming a part of the internal flow path of the supply port 41, and an actuator accommodating portion 24. A through groove portion 24f forming a part of the above is formed.

As shown in FIGS. 7 (g) and 8 (g), the damper member 81 is formed with a discharge side damper 85 and a supply side damper 86. Further, the damper member 81 has a through hole 42 g forming a part of the internal flow path of the discharge port 42, a through hole 41 g forming a part of the internal flow path of the supply port 41, and one of the actuator accommodating portions 24. A through groove portion 24g constituting the portion is formed.

As shown in FIGS. 7 (h) and 8 (h), the damper chamber member 84 is formed with a recess 87j forming the damper chamber 87 and a recess 88j forming the damper chamber 88. Further, in the damper chamber member 84, a through hole 42j forming a part of the internal flow path of the discharge port 42, a through hole 41j forming a part of the internal flow path of the supply port 41, and an actuator accommodating portion 24 A through groove portion 24j forming a part is formed.

As shown in FIGS. 7 (i) and 8 (i), the holding member 25, which is not shown in FIG. 6, has a through hole 41i forming a part of the internal flow path of the supply port 41 and a discharge port 42. A through hole 42i forming a part of the internal flow path of the actuator and a through groove portion 24i forming a part of the actuator accommodating portion 24 are formed.

Piezoelectric elements 12A and 12B are formed on the piezoelectric member 12 as shown in FIGS. 7 (j) and 8 (j).

Next, the liquid discharge head according to the third embodiment of the present invention will be described with reference to FIG. FIG. 9 is a cross-sectional explanatory view in a direction orthogonal to the nozzle arrangement direction of the head.

In the present embodiment, the discharge side damper 85 forming the wall surface of the discharge side common liquid chamber 50 and the supply side damper 86 forming the wall surface of the supply side common liquid chamber 10 are formed by different damper members 81A and 81B. There is.

By using the discharge side damper 85 and the supply side damper 86 as separate members in this way, the degree of freedom in damper arrangement can be increased, and the damper area can be widened (larged).

That is, in the present embodiment, the discharge side damper 85 is arranged on the entire wall surface in the direction orthogonal to the nozzle arrangement direction of the discharge side common liquid chamber 50. Similarly, the upstream common liquid chamber portion 10B of the supply side common liquid chamber 10 is expanded until the entire discharge side common liquid chamber 50 overlaps, and then is orthogonal to the nozzle arrangement direction of the upstream common liquid chamber portion 10B. It is placed on the entire wall surface in the direction.

By increasing the damper area in this way, the damper efficiency is improved.

Further, since the supply side damper 86 is arranged so as to face the direction in which the pressure wave from the individual liquid chamber 6 travels straight in the supply side common liquid chamber 10, the damper efficiency is improved in this respect as well.

Next, the liquid discharge head according to the fourth embodiment of the present invention will be described with reference to FIG. FIG. 10 is a cross-sectional explanatory view in a direction orthogonal to the nozzle arrangement direction of the head.

In the present embodiment, the discharge side common liquid chamber 50 and the supply side common liquid chamber 10 are formed side by side by the common liquid chamber member 20, and the damper member 81 and the damper chamber member 84 are laminated on the common liquid chamber member 20. There is. The damper member 81 forms a discharge side damper 85 that forms the wall surface of the discharge side common liquid chamber 50 and a supply side damper 86 that forms the wall surface of the supply side common liquid chamber 10. The damper chamber member 84 forms the damper chambers 87 and 88.

Even with this configuration, the discharge side damper 85 and the supply side damper 86 can be formed of the same member, and the straight direction of the pressure wave propagating to the discharge side common liquid chamber 50 and the supply side common liquid chamber 10 The discharge side damper 85 and the supply side damper 86 can be arranged so as to face each other.

Next, an example of the device for discharging the liquid according to the present invention will be described with reference to FIGS. 11 and 12. FIG. 11 is an explanatory plan view of a main part of the device, and FIG. 12 is an explanatory side view 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 liquids of, for example, yellow (Y), cyan (C), magenta (M), and black (K). Further, the liquid discharge head 404 is mounted by arranging a nozzle array composed of a plurality of nozzles in the 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 portion 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 fed 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 includes, 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 device configured in this way, the paper 410 is fed onto the transport belt 412 and sucked, and the paper 410 is transported in the sub-scanning direction by the orbital movement of the transport belt 412.

Therefore, by driving the liquid discharge head 404 in response to the image signal while moving the carriage 403 in the main scanning direction, the liquid is discharged to 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. FIG. 13 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.

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. 14 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.

Next, another example of the device for discharging the liquid according to the present invention will be described with reference to FIGS. 15 and 16. FIG. 15 is a schematic explanatory view of the device, and FIG. 16 is a plan explanatory view of the head unit of the device.

This device discharges liquid to the carry-in means 501 for carrying in the continuous medium 510, the guide-transport means 503 for guiding and transporting the continuous medium 510 carried in from the carry-in means 501 to the printing means 505, and the continuous medium 510. It includes a printing means 505 for printing to form an image, a drying means 507 for drying the continuous medium 510, and an discharging means 509 for discharging the continuous medium 510.

The continuous medium 510 is sent out from the original winding roller 511 of the carrying-in means 501, guided and conveyed by the rollers of the carrying-in means 501, the guiding and transporting means 503, the drying means 507, and the discharging means 509, and is guided and conveyed by the winding roller 591 of the discharging means 509. It is wound up at.

In the printing means 505, the continuous medium 510 is conveyed on the transfer guide member 559 facing the head unit 550 and the head unit 555, an image is formed by the liquid discharged from the head unit 550, and the continuous medium 510 is discharged from the head unit 55. Post-treatment is performed with the treatment liquid to be treated.

Here, the head unit 550 is referred to, for example, as a full-line head array 551K, 551C, 551M, 551Y for four colors from the upstream side in the medium transport direction (hereinafter, when the colors are not distinguished, it is referred to as "head array 551". ) Is placed.

Each head array 551 is a liquid discharging means, and discharges black K, cyan C, magenta M, and yellow Y liquids to the conveyed continuous medium 510, respectively. The types and numbers of colors are not limited to this.

The head array 551 is, for example, a plurality of liquid discharge heads (which are also simply referred to as “heads”) 1000 according to the present invention arranged in a staggered pattern on a base member 552, but is not limited thereto. ..

Next, an example of the liquid circulation system in this device will be described with reference to FIG. FIG. 17 is a block explanatory view for explaining the system.

The liquid circulation system 630 includes a main tank 602, a head 1000, a supply tank 631, a circulation tank 632, a compressor 633, a vacuum pump 634, a first liquid pump 635, a second liquid pump 636, a supply side pressure sensor 637, and a circulation side. It is composed of a pressure sensor 638, regulators (R) 639a, 639b and the like.

The supply-side pressure sensor 637 is connected to the supply-side flow path between the supply tank 631 and the head 1000 and connected to the supply port 41 (see FIG. 1) of the head 1000. The circulation side pressure sensor 638 is connected to the discharge side flow path between the head 1000 and the circulation tank 632 and connected to the discharge port 42 (see FIG. 1) of the head 1000.

One of the circulation tanks 632 is connected to the supply tank 631 via the first liquid feed pump 635, and the other of the circulation tank 632 is connected to the main tank 602 via the second liquid feed pump 636.

As a result, the liquid flows from the supply tank 631 through the supply port 41 into the head 1000, is discharged from the discharge port 42, and is discharged to the circulation tank 632. Then, the liquid is circulated by being further sent from the circulation tank 632 to the supply tank 631 by the first liquid feed pump 635.

Further, a compressor 633 is connected to the supply tank 631, and the supply side pressure sensor 637 controls so that a predetermined positive pressure is detected. On the other hand, a vacuum pump 634 is connected to the circulation tank 632, and is controlled so that a predetermined negative pressure is detected by the circulation side pressure sensor 638.

As a result, the negative pressure of the meniscus can be kept constant while circulating the liquid through the head 1000.

Further, when the liquid is discharged from the nozzle 4 of the head 1000, the amount of liquid in the supply tank 631 and the circulation tank 632 decreases. Therefore, the second liquid feeding pump 636 is used to replenish the liquid from the main tank 602 to the circulation tank 632 as appropriate. The timing of liquid replenishment from the main tank 602 to the circulation tank 632 is such that the liquid level in the circulation tank 632 is replenished when the liquid level in the circulation tank 632 falls below a predetermined height. It can be controlled by the detection result of a sensor or the like.

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, etc., for example, inks for inkjets, surface treatment liquids, constituents of electronic elements and light emitting elements, and formation of electronic circuit resist patterns. It can be used for applications such as a liquid for use and a material liquid for three-dimensional modeling.

Piezoelectric actuators (laminated piezoelectric elements and thin-film piezoelectric elements), thermal actuators that use electrothermal 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 an aggregate of parts related to liquid discharge. For example, the "liquid discharge unit" includes a combination of at least one of a head tank, a carriage, a supply mechanism, a maintenance / recovery mechanism, and a main scanning movement mechanism with a liquid discharge head.

Here, "integration" means, for example, a liquid discharge head and a functional component, a mechanism fixed to each other by fastening, adhesion, engagement, etc., or one in which one is movably held with respect to the other. Including. Further, the liquid discharge head, the functional parts, and the mechanism may be detachably attached to each other.

For example, as a liquid discharge unit, there is one in which a liquid discharge head and a head tank are integrated. In addition, there are cases in which 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 liquid discharge head and a carriage integrated.

Further, as a liquid discharge unit, there is a liquid discharge head in which the liquid discharge head and the scanning movement mechanism are integrated by holding the liquid discharge head movably by a guide member forming 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. Through this tube, the liquid of the liquid storage source is supplied to the liquid discharge head.

The main scanning movement mechanism shall also 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 the liquid includes not only a device capable of discharging the liquid to a device to which the liquid can adhere, but also a device for discharging the liquid into the air or the liquid.

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

For example, as a "device that ejects a liquid", an image forming apparatus that ejects ink to form an image on paper, and a three-dimensional object (three-dimensional object) are formed in layers in order to form a three-dimensional object. 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 a 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 "material to which a liquid can adhere" means a material to which a liquid can adhere at least temporarily, such as one that adheres and adheres, and one that adheres and permeates. Specific examples include paper, recording paper, recording paper, film, recording 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, including anything to which the liquid adheres, unless otherwise specified.

The material of the above-mentioned "material to which liquid can be attached" may be paper, thread, fiber, cloth, leather, metal, plastic, glass, wood, ceramics or the like as long as the liquid can be attached 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 a 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 granulation device that granulates fine particles of the raw material by injecting a composition liquid in which the raw material is dispersed in a solution through a nozzle.

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

1 Nozzle plate 2 Flow path plate 3 Vibration plate 4 Nozzle 5 Nozzle communication passage 6 Individual liquid chamber 10 Supply side common liquid chamber 11 piezoelectric actuator 20 Common liquid chamber member 50 Discharge side common liquid chamber 57 Discharge side fluid resistance part 58 Discharge side out-licensing Part 85 Discharge side damper 86 Supply side damper 87 Damper chamber 88 Damper chamber 403 Carriage 404 Liquid discharge head 440 Liquid discharge unit 630 Liquid circulation system 1000 Liquid discharge head

Claims (4)

Multiple nozzles that discharge liquid and
A plurality of individual liquid chambers communicating with the plurality of nozzles, and
A common liquid chamber on the supply side leading to the plurality of individual liquid chambers,
A plurality of discharge channels communicating with each of the plurality of individual liquid chambers,
A common liquid chamber on the discharge side leading to the plurality of discharge channels ,
A discharge-side damper forming the wall surface of the discharge-side common liquid chamber,
A supply-side damper that forms the wall surface of the supply-side common liquid chamber is provided.
The discharge side damper and the supply side damper are integral members.
The supply-side common liquid chamber and the discharge-side common liquid chamber have a portion that overlaps when one is projected onto the other in the direction perpendicular to the nozzle surface.
A liquid discharge head characterized in that at least one of the supply side damper and the discharge side damper is arranged in the overlapping portion. A liquid discharge unit including the liquid discharge head according to claim 1. 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 2 , 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. Liquid discharge head according to claim 1, or an apparatus for discharging a liquid, characterized in that it comprises a liquid discharge unit according to claim 2 or 3.

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