JP2020090013A - Liquid storage tank and droplet discharge head - Google Patents

Abstract

To provide a liquid storage tank which enables air bubbles to be removed from a liquid more easily and reliably, and to provide a droplet discharge head.SOLUTION: A liquid storage tank 20 includes: a liquid storage part 23 which stores a liquid to be supplied to a discharge operation part of a droplet discharge head; and a deaeration passage 29 which discharges air in the liquid storage part 23. The liquid storage part 23 has: an upstream side storage part 23a into which the liquid supplied from the outside flows; a downstream side storage part 23b from which the liquid supplied to the discharge operation part flows; and a filter 231 provided between the upstream side storage part 23a and the downstream side storage part 23b. The deaeration passage 29 is connected to the upstream side storage part 23a. A second supply passage 24 connecting the downstream side storage part 23b to a liquid outflow port leading into the discharge operation part is connected to an upper part of the downstream side storage part 23b.SELECTED DRAWING: Figure 2

Description

The present invention relates to a liquid storage tank and a droplet discharge head.

There is a liquid ejection device that ejects a liquid such as ink from a nozzle at a desired timing and lands it at a desired position. Some liquid storage tanks that supply a liquid to a droplet discharge head provided with a nozzle are provided with a filter. The liquid from which impurities have been removed by this filter is supplied to each nozzle.

In addition, bubbles may be mixed in the liquid in the droplet discharge head. The bubbles may adversely affect the supply and discharge of the liquid. Conventionally, there is a droplet discharge head provided with a path for discharging the bubbles. Patent Document 1 describes a technique for appropriately discharging bubbles remaining on the upstream side of a filter from a bypass path when ink is filled. Further, there is a technique (Patent Document 2) in which a bypass flow path for discharging bubbles is provided on both the upstream side and the downstream side of the filter.

JP, 2011-230337, A JP, 2011-148224, A

However, in the conventional flow path configuration, the bubbles mixed in the liquid on the downstream side of the filter are not properly discharged, and it is difficult to adjust the flow rate because the liquid and air are appropriately discharged before and after the filter. There is a problem that it takes time.

An object of the present invention is to provide a liquid storage tank and a liquid droplet ejection head that can more easily and reliably remove bubbles from a liquid.

In order to achieve the above object, the invention according to claim 1 is
A storage unit for storing the liquid supplied to the discharge operation unit of the droplet discharge head;
A deaeration path for discharging the air inside the reservoir,
Equipped with
The storage part includes a first storage part into which the liquid supplied from the outside flows, a second storage part from which the liquid supplied to the ejection operation part flows out, the first storage part, and the storage part. A filter provided between the second storage parts,
The deaeration path is connected to the first storage section,
A liquid storage tank, wherein a supply path connecting the second storage section and the first outlet of the liquid to the discharge operation section is connected to an upper portion of the second storage section. Is.

The invention according to claim 2 provides the liquid storage tank according to claim 1,
A discharge passage through which the liquid discharged from the discharge operation unit passes,
The deaeration path connects the first storage part and the discharge path.

The invention according to claim 3 provides the liquid storage tank according to claim 2,
The discharge path is provided on one side in a predetermined direction with respect to the storage section,
The supply passage is connected to the second storage portion at an end of the upper portion of the second storage portion near the discharge passage.

The invention according to claim 4 is the liquid storage tank according to claim 2 or 3,
The discharge path is provided on one side in a predetermined direction with respect to the storage section,
The deaeration path is connected to an end of the upper part of the first storage section on the side closer to the discharge path.

The invention according to claim 5 provides the liquid storage tank according to claim 3 or 4,
The first outlet is provided on the opposite side of the discharge path in the predetermined direction with respect to the storage section.

The invention according to claim 6 provides the liquid storage tank according to any one of claims 3 to 5,
In the supply path, a connection end to the second storage section is provided across a width of the second storage section in a direction perpendicular to the predetermined direction in a plane perpendicular to the vertical direction. And

The invention according to claim 7 provides the liquid storage tank according to any one of claims 3 to 6,
The predetermined direction is equal to the longitudinal direction of the storage section in plan view.

The invention according to claim 8 is the liquid storage tank according to any one of claims 1 to 7,
The filter intersects with a plane perpendicular to the vertical direction, is provided in a plane including the longitudinal direction of the storage section, and separates the first storage section and the second storage section from each other. And

Further, the invention according to claim 9 is the liquid storage tank according to any one of claims 1 to 8,
The position where the liquid flows into the first storage part and the position where the supply path is connected to the second storage part are diagonal positions in the storage part. To do.

Further, the invention according to claim 10 is
A droplet discharge head comprising the liquid storage tank according to claim 1.

Further, the invention according to claim 11 is
A discharge operation unit having a nozzle for discharging a liquid,
A liquid storage tank having a storage part for storing the liquid supplied to the discharge operation part, and a degassing path for discharging bubbles from the storage part;
Equipped with
The nozzle ejects the liquid from an opening provided on a predetermined ejection surface of the ejection operation unit,
The storage part includes a first storage part into which the liquid supplied from the outside flows, a second storage part from which the liquid supplied to the ejection operation part flows out, the first storage part, and the storage part. A filter provided between the second storage parts,
The deaeration path is connected to the first storage section,
The supply path connecting the second storage section and the first outlet of the liquid to the discharge operation section in the liquid storage tank is the second storage section in the inward normal direction of the discharge surface. The droplet discharge head is characterized in that it is connected to the upper part of.

According to a twelfth aspect of the invention, there is provided the liquid droplet ejection head according to the eleventh aspect,
The discharge operation unit has a common flow path that communicates with the nozzle and supplies the liquid to the nozzle.
The common flow path has a second outlet that allows the liquid to flow out of the discharge operation unit, separately from the opening of the nozzle,
The liquid storage tank includes a discharge passage through which the liquid flowing out from the second outlet is passed,
The deaeration path connects the first storage part and the discharge path.

According to a thirteenth aspect of the present invention, in the droplet discharge head according to the twelfth aspect,
The common channel extends in a predetermined direction in a plane in which a connection portion of an individual channel connecting the common channel and the nozzle extends in a plane parallel to the ejection surface,
The discharge passage is provided on the second outlet side in the predetermined direction with respect to the storage portion,
The supply passage is connected to the second storage portion at an end on the second outlet side in the predetermined direction.

The invention according to claim 14 is the droplet discharge head according to claim 12 or 13,
The common channel extends in a predetermined direction in a plane in which a connection portion of an individual channel connecting the common channel and the nozzle extends in a plane parallel to the ejection surface,
The discharge passage is provided on the second outlet side in the predetermined direction with respect to the storage portion,
The deaeration passage is connected to the first storage portion at an end on the second outlet side in the predetermined direction.

According to a fifteenth aspect of the present invention, in the droplet discharge head according to the thirteenth or fourteenth aspect,
The first outlet is provided on the side opposite to the second outlet in the predetermined direction with respect to the storage portion.

The invention described in claim 16 is the droplet discharge head according to any one of claims 12 to 15,
The common channel extends in a predetermined direction in a plane in which a connection portion of an individual channel connecting the common channel and the nozzle extends in a plane parallel to the ejection surface,
In the supply path, a connection end to the second storage section is provided across a width of the second storage section in a direction perpendicular to the predetermined direction in a plane parallel to the ejection surface. Characterize.

The invention according to claim 17 is the droplet discharge head according to any one of claims 13 to 16,
The predetermined direction is equal to the longitudinal direction of the storage section in a plan view seen from the inward normal direction.

The invention according to claim 18 provides the droplet discharge head according to any one of claims 11 to 17,
The filter is provided in a plane that includes the longitudinal direction of the storage section and intersects with the ejection surface.

The invention according to claim 19 provides the droplet discharge head according to any one of claims 11 to 18,
The position where the liquid flows into the first storage part and the position where the supply path is connected to the second storage part are diagonal positions in the storage part. To do.

According to the present invention, it is possible to remove air bubbles from a liquid more easily and reliably in the liquid storage tank and the droplet discharge head.

It is a perspective view showing a droplet discharge head of the present embodiment. It is a cross-sectional perspective view seen from the bottom side except the legs of the liquid storage tank. FIG. 6 is a cross-sectional view illustrating an ink flow path of a droplet discharge head. FIG. 6 is a cross-sectional view illustrating an ink flow path of a droplet discharge head. FIG. 6 is a cross-sectional view showing a case where the inkjet head is attached at an angle. It is sectional drawing which shows the modification of an inkjet head.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a perspective view showing a droplet discharge head 100 of this embodiment.

The droplet discharge head 100 is, for example, an inkjet head that is attached to an inkjet recording device and discharges ink. The droplet discharge head 100 includes a discharge operation unit 10, a liquid storage tank 20, and the like.

The discharge operation unit 10 has a nozzle N (see FIGS. 3 and 4), and the bottom surface side (−Z side) is a discharge surface (predetermined discharge surface) in which the nozzle openings are arranged. The ejection operation unit 10 ejects the liquid (ink) supplied from the liquid storage tank 20 from the nozzle N. Further, the ejection operation unit 10 can eject the supplied ink, which has not been ejected from the nozzle, to the liquid storage tank 20. The ejection operation unit 10 further includes a configuration and an electric circuit (not shown) that gives pressure fluctuations for ejecting ink from the nozzles.

The liquid storage tank 20 is attached to the side (+Z side) opposite to the nozzle opening side (ejection surface side) of the ejection operation unit 10. The liquid storage tank 20 includes a supply port 21 (inlet) for ink supplied from an external ink tank, and a liquid storage section 23 (storage section: storage section: FIGS. 3 and 4) for storing (storing) the supplied ink (liquid). ) Is provided, an outflow port 25 (first outflow port) for allowing the ink to flow from the liquid storage unit 23 into the ejection operation unit 10, and an inflow port through which the ink ejected from the ejection operation unit 10 flows. 26, and a discharge port 28 (outlet) for discharging the discharged ink to the outside.

Inside the liquid storage tank 20, there are an ink flow path (supply path) connected from the supply port 21 to the outflow port 25 via the liquid storage section 23, and an ink flow path (discharge path) connected from the inflow port 26 to the discharge port 28. Are provided respectively. The outflow port 25 is connected to the ink inflow port 11 of the ejection operation unit 10, and the inflow port 26 is connected to the ink outflow port 17 (second outflow port) of the ejection operation unit 10. As a result, in the droplet discharge head 100, the ink flow paths from the supply port 21 to the discharge port 28 of the liquid storage tank 20 are connected. The liquid storage tank 20 may be attachable to and detachable from the ejection operation unit 10.

The liquid storage tank 20 has a shape that is long in the Y direction and thin in the X direction when viewed from the upper surface side (the side overlooking the supply port 21 and the discharge port 28), that is, here in plan view (viewed from the +Z direction). Is becoming The supply port 21 and the discharge port 28 are separately arranged near both ends in the longitudinal direction (Y direction) of the liquid storage tank 20. Similarly, the outflow port 25 and the inflow port 26 are separately arranged near both ends in the longitudinal direction (Y direction) of the liquid storage tank 20.

Further, the liquid storage tank 20 is provided here upward with the inward normal direction of the ejection surface as the reference direction (+Z direction), but the case where the liquid storage tank 20 is slightly inclined is not excluded. Further, the mounting surface of the liquid storage tank 20, that is, the surface of the discharging operation unit 10 opposite to the discharging surface does not have to be parallel to the discharging surface, and may have irregularities. Hereinafter, the upper end means the highest position (the Z coordinate is maximum) in the +Z direction, and the upper part means a partial range of the target including this upper end. The lower end means a range including the lowest position (minimum Z coordinate) in the +Z direction, and the lower part means a partial range of an object including the lower end.

The droplet discharge head 100 is provided in the +Z direction with respect to the image forming surface (ink landing surface) of the inkjet recording apparatus, that is, the discharge surface is often parallel to the XY plane, but is not limited to this. .. It may be possible to assume a case where it is provided with a slight inclination (90 degrees or less) in the XZ plane (around the Y axis) and/or in the YZ plane (around the X axis). The positional relationship (vertical relationship) in the vertical direction between the supply port 21 and the discharge port 28 depends on the mounting direction of the droplet discharge head 100.

When rotationally arranged in the XZ plane (around the Y axis), the position of the supply port 21 in the vertical direction is usually the position of the discharge port 28 or less, but the position is not limited to this. Here, it is assumed that the supply port 21 and the discharge port 28 have the same height (that is, the discharge surface is parallel to the horizontal plane and the Z direction is the vertical direction). When the position of the discharge port 28 is provided to be higher than the position of the supply port 21, the bubbles mixed with or remaining in the ink in the ink flow path flow to the discharge port 28 by buoyancy. It will be easier.

FIG. 2 is a cross-sectional perspective view of the inside of the main body 20a of the liquid storage tank 20 as viewed from the bottom side. 3 and 4 are cross-sectional views illustrating the ink flow path of the droplet discharge head 100. FIG. 3 is a cross-sectional view taken along a plane parallel to the YZ plane, and in FIG. 3A, the liquid storage section 23 (downstream side storage section 23b) and the surface including the nozzle N are cut, and FIG. In, the cut is made at the surface including the supply port 21 and the discharge port 28. FIG. 4 is a cross-sectional view taken along a plane parallel to the XZ plane, and FIGS. 4A to 4E are cross-sectional views taken along the cross-section line AA-EE in FIG. 3, respectively.

The liquid storage portion 23, which is provided in the main body portion of the liquid storage tank 20 and stores ink, has an upstream storage portion 23a (first storage portion) and a downstream storage portion 23b (first storage portion) due to the filter 231 provided therein. 2 storage parts) (FIG. 2, FIG. 4(b), FIG. 4(c)). The filter 231 captures foreign matters (foreign matter) in the ink stored in the downstream storage portion 23b. Here, the filter 231 is provided in a plane parallel to the YZ plane, that is, perpendicular to the horizontal plane (direction intersecting the plane vertical to the vertical direction), and extends in the longitudinal direction (a plane including the longitudinal direction). It is provided inside).

The supply port 21 and the upstream accommodation part 23a are connected by a first supply path 22 (FIG. 2, FIG. 3(a), FIG. 3(b), FIG. 4(a)), and are supplied from the outside. Ink flows into the upstream storage portion 23a. The opening end 232 at which the first supply path 22 connects to the upstream accommodation portion 23a is provided below the end of the upstream accommodation portion 23a on the side closer to the supply port 21 in the Y direction (see FIGS. 2 and 3 ( a)). Here, the lower part is a range including the lowermost part also in the vertical direction. Further, the downstream accommodation portion 23b and the outlet 25 are connected by the second supply passage 24 (FIG. 2, FIG. 3(a), FIG. 3(b), FIG. 4(a), and FIG. 4(c). )), the ink supplied to the ejection operation unit 10 flows out from the downstream storage unit 23b. The opening end 233 where the second supply passage 24 connects to the downstream accommodation portion 23b is provided at the upper part of the end of the downstream accommodation portion 23b on the side closer to the discharge port 28 (discharge passage 27) in the Y direction (FIG. 3(a), FIG. 4(c)). In this case, the upper part also becomes the uppermost part in the vertical direction.

Since the opening end 232 and the opening end 233 are provided at diagonal positions in the liquid storage portion 23 (FIG. 2, FIG. 3A, FIG. 4C), the ink flowing in from the opening end 232 is The filter 231 is easily transmitted through a wide range of the liquid storage portion 23. As a result, even if the filter 231 is locally clogged with foreign matters, the ink supply capacity is not significantly reduced. Further, the flow is generated only in a part of the liquid storage portion 23, and thus the ink is prevented from stagnation in the remaining part. The term “diagonal position” as used herein means that an opening is provided so as to include a diagonal vertex, and the opening may be provided on any of the three surfaces forming the vertex (these 3 It may span more than one face).

Here, the supply port 21 and the outflow port 25 are on the same side in the Y direction (predetermined direction), and on the opposite side of the inflow port 26 and the exhaust port 28 (exhaust path 27) (here, the +Y side). ), and the opening end 233 is provided on the side opposite to the supply port 21 and the outflow port 25 in the Y direction (FIGS. 3(a) and 3(b)). In addition, the opening end 233 (the connection end to the second storage portion) has a vertical direction in the vertical direction (XY plane, that is, a plane parallel to the ejection surface) in the vertical direction in the Y direction (X direction). It is provided across the width of the downstream housing portion 23b (FIG. 4(c)). The second supply path 24 extends from the opening end 233 above the downstream housing portion 23b (+Z side) in the Y direction and then bends downward to enter the lower side (−Z side) of the first supply path. It is connected to the outflow port 25 (Fig. 3(a), Fig. 3(b), Fig. 4(a)). At this time, the second supply path 24 and the common flow path 12 have appropriate diameters so as to obtain a flow velocity that can move the bubbles in the ink flowing direction in the downward ink flowing direction against the buoyancy. Stipulated in.

The inflow port 26 and the exhaust port 28 are provided on the same one side in the Y direction (predetermined direction) and on the opposite side (here, the -Y side) from the supply port 21 and the outflow port 25, The inflow port 26 and the discharge port 28 are connected by a discharge path 27 extending in the Z direction (Fig. 3(a), Fig. 3(b), Fig. 4(e)). The discharge path 27 allows the ink discharged from the discharge operation unit 10 to pass through.

A check valve 271 is provided in the middle of the discharge path 27 (FIGS. 3B and 4E ), and ink that has not passed through the filter 231 flows backward and flows into the ejection operation unit 10. To prevent.

The upstream accommodation portion 23a and the discharge passage 27 are connected by a degassing passage 29 (FIG. 3(a), FIG. 3(b), FIG. 4(c), FIG. 4(d)). The deaeration path 29 discharges air (bubbles) from the upstream accommodation section 23a. A filter chamber 29a having a filter 291 is provided in the middle of the deaeration path 29 (FIGS. 3A and 4D). Here, the opening of the degassing passage 29 on the discharge passage 27 side is between the inflow port 26 and the check valve 271. Further, the opening 234 of the deaeration path 29 on the upstream accommodation portion 23a side is provided at the upper end of the upstream accommodation portion 23a and at the end closer to the discharge passage 27 in the Y direction. Thereby, the bubbles easily flow into the degassing passage 29 due to the buoyancy. The filter 231 and the filter 291 may be a continuous chain.

In the ejection operation unit 10, a common flow path 12 (manifold) is connected between the ink inflow port 11 and the ink outflow port 17 (FIG. 3(b)). The common channel 12 communicates with the plurality of nozzles N, and distributes and supplies the ink to each nozzle N through the individual channels 15 (FIG. 4B). The common flow path 12 extends in the Y direction (the above-described predetermined direction) in parallel with the ejection surface at the connection portion with each individual flow path 15. That is, the common flow path 12 in this portion extends parallel to the longitudinal direction of the liquid storage portion 23.

The ink inflow port 11 and the ink outflow port 17 are located on the opposite sides of the common flow path 12 in the Y direction so as to be connected to the outflow port 25 and the inflow port 26 of the liquid storage tank 20, respectively (FIG. 3B. ), FIG. 4(a), FIG. 4(e)). That is, the ink outlet 17 is provided on the opposite side of the liquid containing portion 23 from the outlet 25 in the Y direction, and ink can be discharged from the ejection operation unit 10 separately from the nozzle N.

As described above, the bubbles in the upstream accommodation portion 23 a flow to the discharge passage 27 via the degassing passage 29 and are discharged from the discharge outlet 28. On the other hand, when air bubbles flow into and remain in the downstream housing portion 23b, the air bubbles once flow into the discharge operation unit 10 from the second supply passage 24 and then flow out to the discharge passage 27 via the common flow passage 12. That is, this bubble flows through the same path as the ink that has not been ejected from the nozzle N.

FIG. 5 shows a cross-sectional view of the case where the droplet discharge head 100 is attached at an angle. This cross section is the same as the cross section parallel to the YZ plane shown in FIG.

As shown in FIG. 5A, even in the case where the droplet discharge head 100 is mounted by being rotated 10 degrees counterclockwise around the X axis in the cross section parallel to the YZ plane, the above-described embodiment The open end 233 of the liquid storage tank 20 is maintained at the highest position (upper end position) in the vertical direction in the liquid storage portion 23 (downstream storage portion 23b). When rotating around the X-axis, as described above, the discharge port 28 (the side of the discharge passage 27) is rotated so as to be relatively higher in the vertical direction than the side of the supply port 21 (the first supply passage 22). In order to facilitate the escape of air bubbles, the opening end 233 is provided at the upper end on the discharge port 28 side in the Y direction, so that the opening end 233 is maintained at the upper end position of the liquid storage portion 23 (downstream storage portion 23b). Be done.

Further, even when the droplet discharge head 100 is mounted in a state of being rotated around the Y axis by a predetermined angle (less than 90 degrees), the opening end 233 is similarly maintained at the upper end position in the downstream accommodation portion 23b. When the nozzle surface is arranged so as to face the curved surface (the outer peripheral surface of the cylinder, etc.), the plurality of droplet discharge heads 100 are inclined at different angles around the Y axis, but all the droplet discharge heads. In 100, in the liquid storage tank 20, the open end 233 is located in a range including the upper end of the downstream storage portion 23b.

Further, as shown in FIG. 5B, in the ink jet recording apparatus, when the inclination angle at the time of mounting the droplet discharge head 100 is fixed, the opening end 233 is arranged so that the opening end 233 becomes a horizontal plane. May be inclined with respect to the wall surface (or may be provided so as to drop the apex of the rectangular parallelepiped shape).

FIG. 6 is a cross-sectional view showing a modified example of the droplet discharge head 100. The cross section is the same as FIG. 3(a) and FIG.

Contrary to the example of FIG. 5B, in the case where the droplet discharge head 100 is not mounted by rotating around the X axis, the opening end 233 to the second supply path 24 has the Y axis. It may be provided at the upper end on the supply port 21 side in the direction. Here, accordingly, the opening end 232 of the first supply path 22 to the upstream housing portion 23a is diagonal to the opening end 233 of the liquid housing portion 23, that is, the discharge port 28 side in the Y-axis direction. Is provided at the lower end of.

As described above, the liquid storage tank 20 of the present embodiment has the liquid storage portion 23 that stores the ink to be supplied to the discharge operation portion 10 of the droplet discharge head 100, and the degassing device that discharges the air inside the liquid storage portion 23. And an airway 29. The liquid storage unit 23 includes an upstream storage unit 23a into which ink supplied from the outside flows, a downstream storage unit 23b into which ink supplied to the ejection operation unit 10 flows, an upstream storage unit 23a, and a downstream storage unit. The filter 231, which is provided between the parts 23b, and the deaeration path 29 are connected to the upstream accommodation part 23a, the downstream accommodation part 23b, and the ink outlet 25 to the ejection operation part 10. The second supply path 24 connecting the two is connected to the upper portion of the liquid droplet ejection head 100 in the downstream housing portion 23b.
In this way, in the liquid storage section 23 partitioned by the filter 231, the degassing passage 29 is provided only on the upstream side to bypass the bubbles, and the bubbles are sent from the downstream side storage section 23b to the discharge operation unit 10, Bubbles are discharged through the discharge operation unit 10. At this time, by arranging the open end 233 of the second supply path 24 so as to include the upper end in the vertical direction, bubbles are smoothly generated by the buoyancy in the liquid storage portion 23 having a relatively low flow velocity. Sent to. Thereby, the bubbles can be reliably discharged from the liquid storage portion 23.

Further, the liquid storage tank 20 is provided with a discharge passage 27 through which the ink discharged from the discharge operation unit 10 passes, and the degassing passage 29 connects the upstream storage unit 23 a and the discharge passage 27. As a result, the bubbles discharged from the upstream accommodation portion 23a are removed, and the ink that has passed through the degassing path 29 is merged with the ink that has flowed out without being ejected from the ejection operation unit 10 for efficient recovery ( Can be discharged).

In addition, the discharge passage 27 is provided on one side in the Y direction with respect to the liquid storage portion 23, and the second supply passage 24 is the end of the upper portion of the downstream storage portion 23b that is closer to the discharge passage 27. It is connected to the downstream housing portion 23b. As a result, even if the liquid droplet ejection head 100 to which the liquid storage tank 20 is attached may be attached to be tilted about the X axis, it is normally rotated so that the side of the discharge path 27 is upward in the vertical direction. Therefore, the air in the downstream accommodation portion 23b surely flows into the second supply passage 24 by buoyancy. Therefore, the air can be reliably discharged from the downstream accommodation portion 23b.

Further, the deaeration passage 29 is connected to the end of the upper portion of the upstream accommodation portion 23a on the side closer to the discharge passage 27. Accordingly, when the droplet discharge head 100 is attached to be tilted around the X axis, not only the inside of the downstream housing portion 23b but also the air inside the upstream housing portion 23a is caused to flow into the degassing passage 29 by buoyancy. It is possible to reliably discharge the air.

The outflow port 25 is provided on the opposite side of the discharge passage 27 in the Y-axis direction with respect to the liquid storage portion 23. That is, since the ejection operation unit 10 is connected to both ends of the liquid storage tank 20 and ink is supplied from one side and ink is ejected to the other, the ink flow in the ejection operation unit 10 becomes smooth.

Further, in the second supply path 24, the opening end 233, which is a connection end to the downstream housing portion 23b, is downstream in a direction perpendicular to the Y direction (X direction) in a plane perpendicular to the vertical direction (Z direction). It is provided across the width of the side accommodation portion 23b. As a result, even if the liquid droplet ejection head 100 to which the liquid storage tank 20 is attached is arranged obliquely around the Y-axis, the opening end 233 is maintained at the upper portion (vertical upper end), and the air smoothly and smoothly. The liquid is discharged from the liquid storage portion 23.

Further, the Y direction is equal to the longitudinal direction of the liquid storage portion 23 in plan view. That is, it is possible to obtain the thin liquid storage tank 20 and the ejection operation unit 10, that is, the droplet ejection head 100, which does not take up space in the thickness direction (X-axis direction).

In addition, the filter 231 intersects with a surface (a surface parallel to the XY surface) perpendicular to the vertical direction (Z direction), is provided in a surface including the longitudinal direction (Y direction) of the liquid storage portion 23, and is provided on the upstream side. The accommodation portion 23a and the downstream accommodation portion 23b are separated from each other. As a result, the effective area of the filter 231 can be increased, and ink can pass through efficiently. In particular, even if impurities are locally clogged in the filter 231, the ink passes through many other parts, so that the liquid storage tank 20 having the filter 231 can be used for a long time without deteriorating the performance.

In addition, the position where the ink flows into the upstream storage section 23 a and the position where the second supply path 24 is connected to the downstream storage section 23 b (open end 233) are diagonal in the liquid storage section 23. The position. As a result, a wide ink flow is generated in the liquid storage portion 23, and stagnation at the end can be reduced. Further, this makes it possible to use the wide range of the filter 231 more effectively.

In addition, the droplet discharge head 100 of the present embodiment includes the liquid storage tank 20 described above.
Alternatively, the droplet discharge head 100 according to the present exemplary embodiment includes the discharge operation unit 10 having the nozzles N that discharge ink, the liquid storage unit 23 that stores the ink supplied to the discharge operation unit 10, and the bubbles from the liquid storage unit 23. And a liquid storage tank 20 having a degassing path 29 for discharging the liquid.
The nozzle N ejects ink from an opening provided on the ejection surface (bottom surface) of the ejection operation unit 10, and the liquid storage unit 23 includes an upstream storage unit 23a into which ink supplied from the outside flows and an ejection operation unit. It has a downstream side storage portion 23b from which the ink supplied to the printer 10 flows out, and a filter 231 provided between the upstream side storage portion 23a and the downstream side storage portion 23b. The deaeration path 29 is connected to the upstream accommodation section 23a, and the second supply path 24 connecting the downstream accommodation section 23b and the ink outlet 25 to the ejection operation section 10 in the liquid accommodation tank 20 has an ejection surface. Is connected to the upper part of the downstream accommodation portion 23b in the inward normal direction.
Therefore, in the droplet discharge head 100, it is possible to reliably discharge the air from both upstream and downstream sides of the filter 231.

Further, the ejection operation unit 10 has a common channel 12 (manifold) that communicates with the nozzle N and supplies ink to the nozzle N, and the common channel 12 ejects ink separately from the opening of the nozzle N. It has an ink outlet 17 for flowing out from the operation unit 10. The liquid storage tank 20 is provided with a discharge passage 27 through which the ink flowing out from the ink outlet 17 passes, and the degassing passage 29 connects the upstream storage portion 23 a and the discharge passage 27. Therefore, the air in the upstream accommodation portion 23a is sent to the discharge passage 27 via the degassing passage 29, and the air in the downstream accommodation portion 23b is discharged from the second supply passage 24 via the common flow passage 12 to the discharge passage 27. Sent to. Therefore, the bubbles in the ink on either side of the filter 231 of the liquid storage portion 23 are reliably discharged.

Further, in the common flow channel 12, the connection portion of the individual flow channel 15 that connects the common flow channel 12 and the nozzle N extends in a predetermined direction (Y direction) within a plane parallel to the ejection surface (bottom surface), and the discharge is performed. The passage 27 is provided on the ink outlet 17 side in the Y direction with respect to the liquid containing portion 23, and the second supply passage 24 is an end on the ink outlet 17 side in the Y direction with respect to the downstream containing portion 23b. It is connected to the.
That is, it rises from the bottom of the common flow path 12 extending in the Y direction to the ink outlet 17 and flows out to the discharge path 27 as it is, and the second supply path 24 is connected to this discharge path 27 side of the downstream accommodation portion 23b. By doing so, even if the droplet discharge head 100 is slightly tilted around the X-axis and the discharge path 27 side is high, air is appropriately discharged from the downstream accommodation portion 23b, and the common flow path 12 is also provided. The air is appropriately discharged to the discharge path 27 from.

Further, the deaeration path 29 is connected to the upstream storage portion 23a at the end on the ink outlet 17 side in the Y-axis direction.
As a result, the air in the upstream accommodation portion 23a is easily and reliably discharged to the discharge passage 27, and the air in the common flow passage 12 and the discharge passage 27 is smoothly and surely discharged.

The outlet 25 is provided on the opposite side of the liquid outlet 23 from the ink outlet 17 in the Y-axis direction. As a result, the ink supply side and the ink discharge side are opposite sides in the Y-axis direction (longitudinal direction) of the ejection operation unit 10, so that the ink flow is smooth. In addition, this makes it easier and more reliable to discharge the air from the common flow path 12.

In the common flow channel 12, the connection portion of the individual flow channel 15 that connects the common flow channel 12 and the nozzle N extends in a predetermined direction (Y direction) within a plane parallel to the ejection surface, and the second supply channel Reference numeral 24 denotes the width of the downstream accommodation portion 23b in the direction (X direction) perpendicular to the Y direction in the plane in which the opening end 233 which is the connection end to the downstream accommodation portion 23b is parallel to the ejection surface (XY plane). It is installed over. As a result, even if the liquid droplet ejection head 100 to which the liquid storage tank 20 is attached is arranged obliquely around the Y-axis, the opening end 233 is maintained at the upper portion (vertical upper end), and the air smoothly and smoothly. The liquid is discharged from the liquid storage portion 23.

It should be noted that the present invention is not limited to the above embodiment, and various modifications can be made.
For example, in the above embodiment, the liquid storage tank 20 is provided directly above the ejection surface (+Z side), but it may be provided diagonally above (for example, a position shifted in the ±X direction). Further, the liquid storage tank 20 may be attached so as to be inclined with respect to the inward normal direction of the ejection surface. Further, the shape of the liquid storage portion 23 (downstream storage portion 23b) does not have to be a rectangular parallelepiped shape regardless of the mounting direction. In these cases, the opening end 233 may be provided in a range including the upper surface and the upper end in the +Z direction (inward normal direction) in the mounted state. Further, in the above-described embodiment, the portion including the upper end in the direction perpendicular to the horizontal plane is described as the upper portion on the basis of the case where the ejection surface is horizontal, but the liquid storage tank 20 is attached to the ejection operation unit 10. The upper portion and the lower portion may be determined based on the horizontal plane and the vertical direction when the droplet discharge head 10 is further attached to the reference inkjet recording apparatus and installed in the reference posture.

Further, in the above embodiment, the supply port 21 and the outflow port 25 (ink outflow port 11) are on the same side in the Y direction, and the discharge port 28 and the inflow port 26 (ink outflow port 17) are on the same side. However, the supply port 21 and the discharge port 28 may be provided on opposite sides. Alternatively, the supply port 21 and the discharge port 28 may be provided in a positional relationship such that they are not opposite sides, such as the same side in the Y direction.

Further, in the above-described embodiment, the opening end 233 to which the second supply passage 24 is connected to the downstream accommodation portion 23b is located on the −Y direction end portion of the downstream accommodation portion 23b, that is, on the discharge passage 27 side. Although described as being provided at the end, the position in the Y direction is not limited if the liquid storage tank 20 (inward normal direction of the ejection surface) is not provided so as to be inclined in the −Y direction. Good. The same applies to the opening 234 of the degassing passage 29 on the upstream accommodation portion 23a side. When the shape of the upstream housing portion 23a and the shape of the downstream housing portion 23b are different, only one of them may be provided at the end portion in the -Y direction.

Similarly, in the above embodiment, the opening end 233 to which the second supply path 24 is connected to the downstream housing portion 23b is provided over the entire width of the downstream housing portion 23b in the X direction. When it is not assumed that the liquid storage tank 20 rotates around the Y axis and is inclined in the X direction, the opening end 233 is provided only in a part of the width of the downstream storage portion 23b in the X direction. May be. In addition, when the upper surface of the downstream housing portion 23b is not a flat surface, the opening end 233 is provided in a range in which ink can flow in by buoyancy at any angle according to the maximum value of the rotation angle around the Y axis that is assumed. It should be done.

Further, in the above embodiment, the first supply path 22, the lower part of the second supply path 24, and the discharge path 27 are described as being provided at the same position in the X direction, but they are provided at different positions in the X direction. May be. Further, the upper portion of the second supply passage 24 does not have to be provided directly above the liquid storage portion 23.

Further, although the filters 231 and 291 are arranged perpendicular to the ejection surface in the above-described embodiment, they may have some inclination in the X-axis direction.

Further, in the above-described embodiment, the connection position of the first supply passage 22 to the upstream storage portion 23 a and the connection position of the second supply passage 24 to the downstream storage portion 23 b are diagonal to the liquid storage portion 23. Although described as being in a position, it is not limited to this. For example, each apex of the liquid storage portion 23 is rounded, so that the connection position of the second supply passage 24 may be slightly shifted to be provided at the upper portion of the liquid storage portion 23, or simply from the apex. It may be provided at a deviated position.

Further, the structure of the ejection operation unit 10 is not limited to that of the above embodiment. For example, instead of the bottom surface (−Z side) of the common flow channel 12 (manifold), the connection part to each individual flow channel 15 may be provided and arranged on the side surface (X side). Further, another discharge flow path for further collecting and discharging the ink from the individual flow path 15 may be provided. In this case, normally, the bubbles that have flowed in via the second supply passage 24 do not flow into the sufficiently thin individual flow passage 15 but directly reach the ink outlet 17 from the common flow passage 12.

Further, in the above-described embodiment, it is described that the ink is contained and ejected as the liquid, but the ink may include colorless clear ink or the like. In addition to ink, for example, a thin film such as a protective film, a liquid for forming a three-dimensional structure, a fixing liquid, or the like may be ejected.
In addition, the specific details such as the structure, the configuration, and the arrangement shown in the above-described embodiments can be appropriately changed without departing from the spirit of the present invention.

10 Ejection Operation Section 11 Ink Inlet 12 Common Channel 15 Individual Channel 17 Ink Outlet 20 Liquid Storage Tank 20a Main Body 21 Supply Port 22 First Supply Path 23 Liquid Storage Section 23a Upstream Storage Section 23b Downstream Storage Section 231 Filters 232, 233 Open end 234 Open 24 Second supply path 25 Outflow port 26 Inflow port 27 Discharge path 271 Check valve 28 Discharge port 29 Degassing path 29a Filter chamber 291 Filter 100 Droplet ejection head N Nozzle

Claims (19)

A storage unit for storing the liquid supplied to the discharge operation unit of the droplet discharge head;
A deaeration path for discharging the air inside the reservoir,
Equipped with
The storage part includes a first storage part into which the liquid supplied from the outside flows, a second storage part from which the liquid supplied to the ejection operation part flows out, the first storage part, and the storage part. A filter provided between the second storage parts,
The deaeration path is connected to the first storage section,
A liquid storage tank, wherein a supply path connecting the second storage section and the first outlet of the liquid to the discharge operation section is connected to an upper portion of the second storage section. .. A discharge passage through which the liquid discharged from the discharge operation unit passes,
The liquid storage tank according to claim 1, wherein the deaeration path connects the first storage section and the discharge path. The discharge path is provided on one side in a predetermined direction with respect to the storage section,
The liquid storage tank according to claim 2, wherein the supply path is connected to the second storage section at an end of the upper portion of the second storage section near the discharge path. The discharge path is provided on one side in a predetermined direction with respect to the storage section,
The liquid storage tank according to claim 2 or 3, wherein the deaeration passage is connected to an end of the upper portion of the first storage portion on the side closer to the discharge passage. The liquid storage tank according to claim 3, wherein the first outlet is provided on the opposite side of the discharge path with respect to the storage section in the predetermined direction. In the supply path, a connection end to the second storage section is provided across a width of the second storage section in a direction perpendicular to the predetermined direction in a plane perpendicular to the vertical direction. The liquid storage tank according to any one of claims 3 to 5. The liquid storage tank according to any one of claims 3 to 6, wherein the predetermined direction is equal to a longitudinal direction of the storage section in a plan view. The filter intersects with a plane perpendicular to the vertical direction, is provided in a plane including the longitudinal direction of the storage section, and separates the first storage section and the second storage section from each other. The liquid storage tank according to any one of claims 1 to 7. The position where the liquid flows into the first storage part and the position where the supply path is connected to the second storage part are diagonal positions in the storage part. The liquid storage tank according to any one of claims 1 to 8. A droplet discharge head comprising the liquid storage tank according to claim 1. A discharge operation unit having a nozzle for discharging a liquid,
A liquid storage tank having a storage part for storing the liquid supplied to the discharge operation part, and a degassing path for discharging bubbles from the storage part;
Equipped with
The nozzle ejects the liquid from an opening provided on a predetermined ejection surface of the ejection operation unit,
The storage part includes a first storage part into which the liquid supplied from the outside flows, a second storage part from which the liquid supplied to the ejection operation part flows out, the first storage part, and the storage part. A filter provided between the second storage parts,
The deaeration path is connected to the first storage section,
The supply path connecting the second storage section and the first outlet of the liquid to the discharge operation section in the liquid storage tank is the second storage section in the inward normal direction of the discharge surface. A droplet discharge head characterized in that it is connected to the upper part of. The discharge operation unit has a common flow path that communicates with the nozzle and supplies the liquid to the nozzle.
The common flow path has a second outlet that allows the liquid to flow out of the discharge operation unit, separately from the opening of the nozzle,
The liquid storage tank includes a discharge passage through which the liquid flowing out from the second outlet is passed,
The droplet discharge head according to claim 11, wherein the deaeration path connects the first storage section and the discharge path. The common channel extends in a predetermined direction in a plane in which a connection portion of an individual channel connecting the common channel and the nozzle extends in a plane parallel to the ejection surface,
The discharge passage is provided on the second outlet side in the predetermined direction with respect to the storage portion,
The droplet supply head according to claim 12, wherein the supply path is connected to the second storage section at an end on the second outlet side in the predetermined direction. The common channel extends in a predetermined direction in a plane in which a connection portion of an individual channel connecting the common channel and the nozzle extends in a plane parallel to the ejection surface,
The discharge passage is provided on the second outlet side in the predetermined direction with respect to the storage portion,
The droplet discharge head according to claim 12 or 13, wherein the degassing passage is connected to the first storage portion at an end on the second outlet side in the predetermined direction. .. 15. The droplet discharge head according to claim 13, wherein the first outlet is provided on the opposite side of the second outlet with respect to the storage portion in the predetermined direction. The common channel extends in a predetermined direction in a plane in which a connection portion of an individual channel connecting the common channel and the nozzle extends in a plane parallel to the ejection surface,
In the supply path, a connection end to the second storage section is provided across a width of the second storage section in a direction perpendicular to the predetermined direction in a plane parallel to the ejection surface. The droplet discharge head according to any one of claims 12 to 15, which is characterized. The liquid droplet ejection head according to claim 13, wherein the predetermined direction is equal to a longitudinal direction of the storage section in a plan view when viewed from the inward normal direction. The droplet discharge head according to claim 11, wherein the filter is provided in a plane that includes a longitudinal direction of the storage portion and intersects with the discharge plane. The position where the liquid flows into the first storage part and the position where the supply path is connected to the second storage part are diagonal positions in the storage part. The droplet discharge head according to any one of claims 11 to 18.