Patent Application
20230294400
The present application is based on, and claims priority from JP Application Serial Number 2022-042247, filed Mar. 17, 2022, the disclosure of which is hereby incorporated by reference herein in its entirety.
The present disclosure relates to a liquid ejecting head and a liquid ejecting apparatus.
A liquid ejecting apparatus typified by an ink jet printer generally includes a liquid ejecting head that ejects a liquid such as ink. For example, JP-A-2008-149617 describes a head having a configuration in which a pressure chamber plate, a communication port plate, a supply port plate, and a reservoir plate are laminated in this order. Here, the pressure chamber plate partitions a pressure chamber. A third communication port and a supply-side communication port are formed on the communication port plate. A supply port and a second communication port are formed on the supply port plate. A reservoir and a first communication port are formed on the reservoir plate. The third communication port communicates with the pressure chamber, and functions as a nozzle communication port communicating with a nozzle in a series of the first communication port and the second communication port. The supply-side communication port communicates with the pressure chamber, and functions as an ink supply port that supplies ink from the reservoir to the pressure chamber together with the supply port.
In the head described in JP-A-2008-149617, although a thickness of the supply port plate is extremely thin, the supply port plate is not bonded to the reservoir plate in the vicinity of the supply port over a wide area in a circumferential direction of the supply port. Therefore, when the pressure chamber plate is bonded to the communication port plate, the supply port plate may be deformed by a load at the time of bonding. When such deformation occurs, a shape of the supply port formed by fine processing is distorted, and as a result, a supply amount of the ink to the pressure chamber varies, which may adversely affect ejection characteristics.
According to an aspect of the present disclosure, there is provided a liquid ejecting head including: a pressure chamber substrate having a pressure chamber for accommodating a liquid; a drive element that imparts a pressure fluctuation to the liquid in the pressure chamber; a communication substrate having a supply communication flow path communicating with the pressure chamber and a nozzle communication flow path communicating with the pressure chamber and communicating with a nozzle for ejecting a liquid at a position different from the supply communication flow path; and a coupling substrate disposed between the pressure chamber substrate and the communication substrate, the coupling substrate having a supply port located between the pressure chamber and the supply communication flow path and a discharge port located between the pressure chamber and the nozzle communication flow path, in which the pressure chamber substrate has a partition wall that partitions the pressure chamber, and the communication substrate includes a first region bonded to the coupling substrate and overlapping the pressure chamber between the supply communication flow path and the nozzle communication flow path when viewed in a thickness direction of the pressure chamber substrate, and a second region bonded to the coupling substrate and overlapping the partition wall at a position adjacent to the first region via an opening of the supply communication flow path when viewed in the thickness direction of the pressure chamber substrate.
According to another aspect of the present disclosure, there is provided a liquid ejecting apparatus including: the above-described liquid ejecting head; and a liquid container storing a liquid supplied to the liquid ejecting head.
Hereinafter, preferred embodiments according to the present disclosure will be described with reference to accompanying drawings. In the drawings, the dimensions and scale of each section are appropriately different from the actual ones, and some sections are schematically illustrated for facilitating understanding. In addition, the scope of the present disclosure is not limited to these forms unless it is stated in the following description that the present disclosure is particularly limited.
The following description will be given appropriately using X axis, Y axis and Z axis that intersect each other for convenience. Further, one direction along the X axis is an X1 direction, and a direction opposite to the X1 direction is an X2 direction. In a similar manner, directions opposite to each other along the Y axis are a Y1 direction and a Y2 direction. Further, directions opposite to each other along the Z axis are a Z1 direction and a Z2 direction.
Here, typically, the Z axis is a vertical axis, and the Z2 direction corresponds to a downward direction in the vertical direction. Here, the Z axis does not have to be a vertical axis and may be inclined with respect to the vertical axis. The X axis, the Y axis, and the Z axis are typically orthogonal to each other, but are not limited to this, and may intersect at an angle within a range of, for example, 80° or more and 100° or less. In the following, viewing in the direction along the Z axis may be referred to as “plan view”.
As illustrated in
The liquid container 110 is a container for storing an ink. Specific embodiments of the liquid container 110 include, for example, a cartridge that is attachable to and detachable from the liquid ejecting apparatus 100, a bag-shaped ink package made of a flexible film, and an ink tank that can be refilled with the ink. The type of the ink stored in the liquid container 110 is optional.
Although not illustrated in the drawing, the liquid container 110 of the present embodiment includes a first liquid container and a second liquid container. The first liquid container stores a first ink. The second liquid container stores a second ink having a type different from that of the first ink. For example, the first ink and the second ink are inks with different colors from each other. The first ink and the second ink may be the same type of ink.
The control unit 120 controls an operation of each element of the liquid ejecting apparatus 100. The control unit 120 includes, for example, one or a plurality of processing circuits such as a central processing unit (CPU) or a field programmable gate array (FPGA) and one or a plurality of storage circuits such as a semiconductor memory. The storage circuit stores various programs and various data. The processing circuit realizes various controls by executing the programs and using the data as appropriate.
The transport mechanism 130 transports the medium M in a direction DM under control of the control unit 120. The direction DM of the present embodiment is the Y2 direction. In an example illustrated in
Under the control of the control unit 120, the liquid ejecting module 140 ejects the ink, which is supplied from the liquid container 110 through the circulation mechanism 160, from each of the plurality of nozzles to the medium M in the Z2 direction. The liquid ejecting module 140 is a line head having a plurality of liquid ejecting heads 150 disposed such that the plurality of nozzles are distributed throughout the entire range of the medium M in the direction of the X axis. The plurality of liquid ejecting heads 150 are collectively supported by a support (not illustrated), and a positional relationship between the plurality of liquid ejecting heads 150 is fixed.
An image of ink is formed on the surface of the medium M by ejecting the ink from the plurality of liquid ejecting heads 150 in parallel with the transport of the medium M by the transport mechanism 130. It should be noted that the plurality of nozzles of one liquid ejecting head 150 may be disposed so as to be distributed throughout the entire range of the medium M in the direction along the X axis. In such a case, for example, the liquid ejecting module 140 is constituted of one liquid ejecting head 150. The number of liquid ejecting heads 150 included in the liquid ejecting module 140 is not limited to the example illustrated in
The liquid container 110 is coupled to the liquid ejecting module 140 through the circulation mechanism 160. The circulation mechanism 160 supplies the ink to the liquid ejecting module 140 under the control of the control unit 120, and recovers the ink discharged from the liquid ejecting module 140 in order to resupply the ink to the liquid ejecting module 140. The circulation mechanism 160 has, for example, a sub tank that stores the ink, a supply flow path for supplying the ink from the sub tank to the liquid ejecting module 140, a recovery flow path for recovering the ink from the liquid ejecting module to the sub tank, and a pump for appropriately flowing the ink. The sub tank, the supply flow path, the recovery flow path, and the pump are provided for each container of the above-mentioned first liquid container and second liquid container. By the operation of the circulation mechanism 160 as described above, it is possible to suppress an increase in viscosity of the ink and reduce retention of air bubbles in the ink.
The flow path structure 151 is a structure in which a flow path for flowing the ink between the circulation mechanism 160 and the plurality of head chips 10 are provided inside the flow path structure 151. As illustrated in
Here, although not illustrated in
Each of the coupling tubes 151a, 151b, 151c, and 151d is a tubular body protruding in the Z1 direction and is coupled to the circulation mechanism 160. The coupling tube 151a is a tubular body constituting a flow path through which the first ink is supplied to first supply flow path. The coupling tube 151b is a tubular body constituting a flow path through which the second ink is supplied to the second supply flow path. Meanwhile, the coupling tube 151c is a tubular body constituting a flow path through which the first ink is discharged from the first discharge flow path. The coupling tube 151d is a tubular body constituting a flow path through which the second ink is discharged from the second discharge flow path. The hole 151e is a hole into which a connector 152c to be described later is inserted.
The wiring substrate 152 is a mount component that electrically couples the plurality of head chips 10 and an assembly substrate 155b to be described later. The wiring substrate 152 is, for example, a rigid wiring substrate. The wiring substrate 152 is disposed between the flow path structure 151 and the holder 153. The connector 152c is provided on a surface of the wiring substrate 152 facing the flow path structure 151. The connector 152c is a coupling component coupled to the assembly substrate 155b to be described later. The wiring substrate 152 is provided with a plurality of holes 152a and a plurality of opening portions 152b. Each hole 152a is a hole for causing coupling between the flow path structure 151 and the holder 153. Each opening portion 152b is a hole through which a wiring substrate 18 of the head chip 10 described later is passed. The wiring substrate 18 is coupled to a surface of the wiring substrate 152 facing the Z1 direction.
The holder 153 is a structure that accommodates and supports the plurality of head chips 10. The holder 153 is made of, for example, a resin material, a metal material, or the like. The holder 153 has a plate shape which extends in a direction perpendicular to the Z axis. The holder 153 is provided with a coupling tube 153a, a coupling tube 153b, a plurality of coupling tubes 153c, a plurality of coupling tubes 153d, and a plurality of wiring holes 153e. Although not illustrated, a plurality of recess portions for accommodating the plurality of head chips 10 are provided on the surface of the holder 153 facing the Z2 direction.
In the example illustrated in
Here, although not illustrated in
In the example illustrated in
The coupling tubes 153a, 153b, 153c, and 153d are tubular protrusions protruding in the Z1 direction. More specifically, the coupling tube 153a is a tubular body constituting a flow path through which the first ink is supplied to the first distribution supply flow path, and communicates with the first supply flow path of the flow path structure 151. The coupling tube 153b is a tubular body constituting a flow path through which the second ink is supplied to the second distribution supply flow path, and communicates with the second supply flow path of the flow path structure 151. Meanwhile, the coupling tube 153c is a tubular body constituting a flow path through which the first ink is discharged from the first individual discharge flow path, and communicates with the first discharge flow path of the flow path structure 151. The coupling tube 153d is a tubular body constituting a flow path through which the second ink is discharged from the second individual discharge flow path, and communicates with the second discharge flow path of the flow path structure 151. The wiring hole 153e is a hole through which the wiring substrate 18 of the head chip 10 is passed.
Each head chip 10 ejects an ink. Although not illustrated in
The fixing plate 154 is a plate member which fixes the plurality of head chips 10 to the holder 153. Specifically, the fixing plate 154 is disposed with the plurality of head chips 10 sandwiched between the fixing plate 154 and the holder 153, and is fixed to the holder 153 with an adhesive. The fixing plate 154 is made of, for example, a metal material. The fixing plate 154 is provided with a plurality of opening portions 154a for exposing the nozzles of the plurality of head chips 10. In the example illustrated in
The base 155 is a member for collectively holding the flow path structure 151, the wiring substrate 152, the holder 153, the plurality of head chips 10, and the fixing plate 154. The base 155 has a main body 155a, an assembly substrate 155b, and a cover 155c.
The main body 155a holds the flow path structure 151 and the wiring substrate 152 disposed between the base 155 and the holder 153 by being fixed to the holder 153 through screwing or the like. The main body 155a is made of, for example, a resin material or the like. The main body 155a has a plate-shaped portion facing the plate-shaped portion of the flow path structure 151 described above, and the plate-shaped portion is provided with a plurality of holes 155d into which the coupling tubes 151a, 151b, 151c, and 151d described above are inserted. The main body 155a has a portion extending in the Z2 direction from the plate-shaped portion, and a flange 155e for fixing to a support (not illustrated) is provided at the tip of the portion.
The assembly substrate 155b is a mount component that electrically couples the control unit 120 and the wiring substrate 152 described above. The assembly substrate 155b is, for example, a rigid wiring substrate. The cover 155c is a plate-shaped member which protects the assembly substrate 155b and fixes the assembly substrate 155b to the main body 155a. The cover 155c is made of, for example, a resin material or the like, and is fixed to the main body 155a through screwing or the like.
Here, the V axis is an axis along an arrangement direction of the plurality of nozzles N to be described later, and is an axis which is obtained by rotating the Y axis around the Z axis at a predetermined angle. The W axis is an axis which is obtained by rotating the X axis around the Z axis at the predetermined angle. Therefore, the V axis and the W axis are typically orthogonal to each other, but are not limited to this, and may intersect at an angle within a range of, for example, 80° or more and 100° or less. The predetermined angle, that is, the angle which is formed by the V axis and the Y axis, or the angle which is formed by the W axis and the X axis is, for example, within the range of 40° or more and 60° or less.
First, a flow path provided in the head chip 10 will be described. As illustrated in
The head chip 10 has a surface facing the medium M, and the plurality of nozzles N are provided on the surface. The plurality of nozzles N are arranged along the V axis. Each of the plurality of nozzles N ejects the ink in the Z2 direction. Here, the plurality of nozzles N are arranged at equal intervals at a predetermined pitch.
The individual flow path P communicates with each of the plurality of nozzles N. Each of the plurality of individual flow paths P extends along the W axis and communicates with the nozzles N different from each other. The plurality of individual flow paths P are arranged along the V axis.
Each individual flow path P includes a pressure chamber Ca, a pressure chamber Cb, a nozzle flow path Nf, a supply communication flow path Ra1, a supply communication flow path Ra2, a nozzle communication flow path Na1, a nozzle communication flow path Na2, supply ports Sa1 and Sa2, and discharge ports Ve1 and Ve2.
Each of the pressure chamber Ca and the pressure chamber Cb in each individual flow path P extends along the W axis and is a space in which the ink ejected from the nozzle N communicating with the individual flow path P is stored. In an example illustrated in
In each individual flow path P, the pressure chamber Ca communicates with the nozzle flow path Nf via the discharge port Ve1 and the nozzle communication flow path Na1. Meanwhile, the pressure chamber Cb communicates with the nozzle flow path Nf via the discharge port Ve2 and the nozzle communication flow path Na2. In the following, when the nozzle communication flow path Na1 and the nozzle communication flow path Na2 are not particularly distinguished, each of these may be referred to as a “nozzle communication flow path Na”. Further, when the discharge port Ve1 and the discharge port Ve2 are not particularly distinguished, each of these may be referred to as a “discharge port Ve”.
In each individual flow path P, the nozzle flow path Nf is a space which extends along the W axis. The plurality of nozzle flow paths Nf are arranged along the V axis at intervals from each other. The nozzle N is provided in each nozzle flow path Nf. In each nozzle flow path Nf, the ink is ejected from the nozzle N by changing the pressure in the pressure chamber Ca and the pressure chamber Cb described above.
The common liquid chamber R1 and the common liquid chamber R2 communicate with the plurality of individual flow paths P. Here, the pressure chamber Ca communicates with the common liquid chamber R1 via the supply port Sa1 and the supply communication flow path Ra1. The pressure chamber Cb communicates with the common liquid chamber R2 via the supply port Sa2 and the supply communication flow path Ra2. In the following, when the supply communication flow path Ra1 and the supply communication flow path Ra2 are not particularly distinguished, each of these may be referred to as a “supply communication flow path Ra”. Further, when the supply port Sa1 and the supply port Sa2 are not particularly distinguished, each of these may be referred to as a “supply port Sa”.
Each of the common liquid chamber R1 and the common liquid chamber R2 is a space which extends along the V axis throughout the entire range in which the plurality of nozzles N are distributed. Here, the common liquid chamber R1 is coupled to an end of each individual flow path P in the W2 direction. The common liquid chamber R1 stores the ink for supplying to each individual flow path P.
Meanwhile, the common liquid chamber R2 is coupled to an end of each individual flow path P in the W1 direction. The common liquid chamber R2 stores the ink discharged from each individual flow path P without being ejected.
The common liquid chamber R1 is provided with a supply port I01. The supply port I01 is a tube path for introducing ink into the common liquid chamber R1 from the first distribution supply flow path or the second distribution supply flow path of the holder 153. Meanwhile, the common liquid chamber R2 is provided with a discharge port 102. The discharge port 102 is a tube path for discharging ink from the common liquid chamber R2 to the first individual discharge flow path or the second individual discharge flow path of the holder 153. In the following, when the common liquid chamber R1 and the common liquid chamber R2 are not particularly distinguished, each of these may be referred to as a “common liquid chamber R”.
As illustrated in
The nozzle substrate 11, the communication substrate 12, the coupling substrate 21, the pressure chamber substrate 13, and the vibration plate 14 are laminated in this order in the Z1 direction. Each of the members extends along the V axis and is manufactured, for example, by processing a silicon single crystal substrate using a semiconductor processing technique. The members are bonded to each other by an adhesive or the like. It should be noted that another layer such as an adhesive layer or a substrate may be appropriately interposed between two adjacent members among the members.
The plurality of nozzles N are provided on the nozzle substrate 11. Each of the plurality of nozzles N is a hole that penetrates the nozzle substrate 11.
The communication substrate 12 is provided with a portion of each of the common liquid chamber R1 and the common liquid chamber R2, the nozzle flow path Nf, the nozzle communication flow path Na1, the nozzle communication flow path Na2, the supply communication flow path Ra1, and the supply communication flow path Ra2. A portion of each of the common liquid chamber R1 and the common liquid chamber R2 is a space for penetrating the communication substrate 12. The vibration absorbing body 20 that blocks the opening by the space is provided on a surface of the communication substrate 12 facing the Z2 direction.
The vibration absorbing body 20 is a layered member made of an elastic material. The vibration absorbing body 20 constitutes a portion of the wall surface of each of the common liquid chamber R1 and the common liquid chamber R2, and absorbs the pressure fluctuation in the common liquid chamber R1 and the common liquid chamber R2.
The nozzle flow path Nf is a space in a groove provided on a surface of the communication substrate 12 facing the Z2 direction. Here, the nozzle substrate 11 constitutes a portion of the wall surface of the nozzle flow path Nf.
Each of the nozzle communication flow path Na1 and the nozzle communication flow path Na2 is a space that penetrates the communication substrate 12.
Each of the supply communication flow path Ra1 and the supply communication flow path Ra2 is a space that penetrates the communication substrate 12. Here, one end of the supply communication flow path Ra1 is opened on a surface of the communication substrate 12 facing the Z1 direction. Meanwhile, the other end of the supply communication flow path Ra1 is an upstream end of the individual flow path P in the direction in which the ink flows by the circulation mechanism 160, and is open on the wall surface of the common liquid chamber R1 in the communication substrate 12. On the other hand, one end of the supply communication flow path Ra2 is opened on the surface of the communication substrate 12 facing the Z1 direction. Meanwhile, the other end of the supply communication flow path Ra2 is an end on the downstream of the individual flow path P in the direction in which the ink flows by the circulation mechanism 160, and is open on the wall surface of the common liquid chamber R2 in the communication substrate 12.
The pressure chamber substrate 13 is provided with the pressure chambers Ca and the pressure chambers Cb of the plurality of individual flow paths P. Each of the pressure chamber Ca and the pressure chamber Cb penetrates the pressure chamber substrate 13 and is a gap between the communication substrate 12 and the vibration plate 14.
Here, the coupling substrate 21 is interposed between the pressure chamber substrate 13 and the communication substrate 12. The coupling substrate 21 is provided with holes for the supply ports Sa1 and Sa2 and the discharge ports Ve1 and Ve2 to penetrate in the thickness direction. The coupling substrate 21 and related matters will be described in detail later with reference to
The vibration plate 14 is a plate-shaped member which is able to elastically vibrate. The vibration plate 14 is a laminate including, for example, a first layer made of silicon oxide (SiO2) and a second layer made of zirconium oxide (ZrO2). Here, another layer such as a metal oxide may be interposed between the first layer and the second layer. A portion or all of the vibration plate 14 may be integrally made of the same material as the pressure chamber substrate 13. For example, the vibration plate 14 and the pressure chamber substrate 13 can be integrally formed by selectively removing a portion in the thickness direction of the region corresponding to the pressure chamber C in the plate-shaped member having a predetermined thickness. The vibration plate 14 may be constituted of a layer of a single material.
The plurality of drive elements 15 corresponding to different pressure chambers C are installed on a surface of the vibration plate 14 facing the Z1 direction. Each drive element 15 is a piezoelectric element, and is, for example, configured by laminating a first electrode and a second electrode facing each other and a piezoelectric layer disposed between the electrodes. Each drive element 15 ejects the ink in the pressure chamber C from the nozzle N by changing the pressure of the ink in the pressure chamber C. The drive element 15 vibrates the vibration plate 14 due to deformation thereof when a driving signal Com is supplied. With the vibration, the pressure chamber C expands and contracts. Therefore, the pressure of the ink in the pressure chamber C fluctuates. The drive element 15 may be a heat generating element that changes the pressure of the ink by generating air bubbles inside the pressure chamber C by heat.
The case 16 is a case that stores the ink. The case 16 is provided with a space constituting a remaining portion other than a portion provided on the communication substrate 12 for each of the common liquid chamber R1 and the common liquid chamber R2.
The protective plate 17 is a plate-shaped member provided on the surface of the vibration plate 14 facing the Z1 direction, protects the plurality of drive elements 15, and reinforces mechanical strength of the vibration plate 14. Here, a space for accommodating the plurality of drive elements 15 is formed between the protective plate 17 and the vibration plate 14.
The wiring substrate 18 is mounted on the surface of the vibration plate 14 facing the Z1 direction, and is a mount component that electrically couples the control unit 120 and the head chip 10. For example, it is preferable that a flexible wiring substrate 18 such as a flexible printed circuit (FPC) or a flexible flat cable (FFC) is used. The drive circuit 19 described above is mounted on the wiring substrate 18.
In the head chip 10 having the above configuration, the ink is distributed to the common liquid chamber R1, the supply communication flow path Ra1, the supply port Sa1, the pressure chamber Ca, the discharge port Ve1, the nozzle communication flow path Na1, the nozzle flow path Nf, the nozzle communication flow path Na2, the discharge port Ve2, the pressure chamber Cb, the supply port Sa2, the supply communication flow path Ra2, and the common liquid chamber R2 in the order by the operation of the circulation mechanism 160 described above.
The pressures of the pressure chamber Ca and the pressure chamber Cb are changed by simultaneously driving the drive element 15 corresponding to both the pressure chamber Ca and the pressure chamber Cb by the driving signal Com from the drive circuit 19. Thereby, the ink is ejected from the nozzle N in accordance with the pressure fluctuation thereof.
As illustrated in
An opening area of the supply port Sa is smaller than an opening area of the discharge port Ve. Therefore, since a flow path resistance of the supply port Sa is higher than a flow path resistance of the discharge port Ve, the ink in the pressure chamber C is more likely to flow into the discharge port Ve than the supply port Sa. As a result, the ink can be efficiently ejected from the nozzle N by the pressure fluctuation of the ink in the pressure chamber C caused by driving the drive element 15.
Here, from the viewpoint of efficiently ejecting ink from the nozzle N, preferably, a width Wa of the supply port Sa is within a range of 0.1 times or more and 0.5 times or less with respect to a width We of the discharge port Ve. Specifically, the width Wa of the supply port Sa is in the range of 5 μm or more and 50 μm or less, preferably in the range of 10 μm or more and 40 μm or less, and these dimensions may be adjusted according to the viscosity of the ink and the like.
In the example illustrated in
Further, while the opening area of the discharge port Ve is about the same as the opening area of the nozzle communication flow path Na, the opening area of the supply port Sa is smaller than the opening area of the supply communication flow path Ra. Therefore, compared to a configuration in which the opening area of the supply communication flow path Ra is set to about the same as the opening area of the supply port Sa, it is possible to simplify the processing of the communication substrate 12 at the time of manufacturing. That is, when the opening area of the supply communication flow path Ra is formed to be small, more accurate pilot hole drilling is required, but this is not necessary and processing at low cost becomes possible.
Further, a thickness t3 of the coupling substrate 21 is thinner than each of a thickness t1 of the communication substrate 12 and a thickness t2 of the pressure chamber substrate 13. Therefore, the supply port Sa and the discharge port Ve can be provided on the coupling substrate 21 with high accuracy. As a result, it is possible to reduce variations in the ejection characteristics of the liquid ejecting head 150 for each nozzle N. The ejection characteristics are general terms for volume and velocity of the droplets ejected from the nozzle N, a timing at which the droplets ejected from the nozzle N, and the like when a pressure fluctuation is imparted to the ink in the pressure chamber C by driving the drive element 15. Here, from the viewpoint of improving the dimensional accuracy of the supply port Sa and the discharge port Ve, the thickness t3 is preferably 10 μm or more and 50 μm or less.
The constituent material of the coupling substrate 21 is not particularly limited, and for example, includes silicon, silicon oxide, silicon nitride, silicon oxynitride, a metal such as stainless steel, a metal oxide such as tantalum oxide, a photosensitive resist film, or the like.
When silicon is used as a constituent material of the coupling substrate 21, in a case where each of the communication substrate 12 and the pressure chamber substrate 13 is composed of silicon, the coupling substrate 21 can be bonded to both or one of the communication substrate 12 and the pressure chamber substrate 13 through direct bonding without using a coating type adhesive. Therefore, it is possible to eliminate both the adhesive between the communication substrate 12 and the coupling substrate 21 and the adhesive between the coupling substrate 21 and the pressure chamber substrate 13, or one of the adhesives, and it is possible to prevent the adverse effect of blocking the supply port Sa and the like with the adhesive. Further, even though tantalum oxide is used as a constituent material of the coupling substrate 21, when each of the communication substrate 12 and the pressure chamber substrate 13 is composed of tantalum oxide, the coupling substrate 21 can be bonded to each of the communication substrate 12 and the pressure chamber substrate 13 through direct bonding without using a coating type adhesive. Further, even though a photosensitive resist film is used as a constituent material of the coupling substrate 21, regardless of the constituent materials of the communication substrate 12 and the pressure chamber substrate 13, the coupling substrate 21 can be bonded to both or one of the communication substrate 12 and the pressure chamber substrate 13 by an adhesive force of the photosensitive resist film without using a coating type adhesive.
The pressure chamber substrate 13 bonded to the surface of the above coupling substrate 21 facing the Z1 direction has a partition wall 13a for partitioning the pressure chamber C. The partition wall 13a is a portion of the pressure chamber substrate 13 that surrounds the pressure chamber C in a plan view and covers the entire area of the pressure chamber substrate 13 in the thickness direction. A surface of the partition wall 13a facing the Z2 direction is coupled to the coupling substrate 21.
Meanwhile, the communication substrate 12 bonded to the surface of the coupling substrate 21 facing the Z2 direction is bonded to the coupling substrate 21 over a wide area in a circumferential direction of the supply port Sa in the vicinity of the supply port Sa. Therefore, when the pressure chamber substrate 13 is bonded to the coupling substrate 21, deformation of the coupling substrate 21 can be reduced due to a load at the time of bonding. Therefore, it is possible to reduce the deterioration of the ejection characteristics due to the deformation.
Specifically, as illustrated in
As described above, the liquid ejecting head 150 includes the pressure chamber substrate 13, the drive element 15, the communication substrate 12, and the coupling substrate 21. The pressure chamber substrate 13 has the pressure chamber C for accommodating ink, which is an example of a “liquid”. The drive element 15 imparts a pressure fluctuation to the ink in the pressure chamber C. The communication substrate 12 has the supply communication flow path Ra communicating with the pressure chamber C and the nozzle communication flow path Na that communicates with the pressure chamber C at a position different from the supply communication flow path Ra and also communicates with the nozzle N for ejecting ink. The coupling substrate 21 Is disposed between the pressure chamber substrate 13 and the communication substrate 12 in the direction along the Z axis, and has the supply port Sa located between the pressure chamber C and the supply communication flow path Ra in the direction along the Z axis and the discharge port Ve located between the pressure chamber C and the nozzle communication flow path Na in the direction along the Z axis.
Here, the pressure chamber substrate 13 has the partition wall 13a that partitions the pressure chamber C. The communication substrate 12 has the first region RE1 and the second region RE2. The first region RE1 is bonded to the coupling substrate 21 and overlaps the pressure chamber C between the supply communication flow path Ra and the nozzle communication flow path Na when viewed in the thickness direction of the pressure chamber substrate 13.
The second region RE2 is bonded to the coupling substrate 21 and overlaps the partition wall 13a at a position adjacent to the first region RE1 via the opening of the supply communication flow path Ra when viewed in the thickness direction of the pressure chamber substrate 13. That is, when viewed in the thickness direction of the pressure chamber substrate 13, the supply port Sa and the opening of the supply communication flow path Ra overlap each other, and the supply port Sa and the opening of the supply communication flow path Ra are located between the first region RE1 and the second region RE2 in the direction along the W axis.
In the above liquid ejecting head 150, the first region RE1 and the second region RE2 of the coupling substrate 21 are coupled to the communication substrate 12 over a wide area in the circumferential direction of the supply port Sa in the vicinity of the supply port Sa. Therefore, an area in which the load from the pressure chamber substrate 13 is supported by the single layer of the coupling substrate 21 can be reduced as compared with the configuration of the related art that does not have the second region RE2. As a result, it is possible to reduce the deterioration of the ejection characteristics due to the deformation of the coupling substrate 21.
Here, as described above, the thickness t3 of the coupling substrate 21 is thinner than the thickness t2 of the pressure chamber substrate 13. In such a case, the effect of reducing the deformation of the coupling substrate 21 by the first region RE1 and the second region RE2 becomes remarkable.
Further, as described above, the thickness t3 of the coupling substrate 21 is thinner than the thickness t1 of the communication substrate 12. In such a case, the effect of reducing the deformation of the coupling substrate 21 by the first region RE1 and the second region RE2 becomes remarkable.
Further, when a Young's modulus of the material constituting the coupling substrate 21 is equal to or less than a Young's modulus of the material constituting the pressure chamber substrate 13 or equal to or less than a Young's modulus of the material constituting the communication substrate 12, the effect of reducing the deformation of the coupling substrate 21 by the first region RE1 and the second region RE2 is remarkable.
Further, as described above, when the opening area of the supply port Sa is smaller than the opening area of the supply communication flow path Ra, the effect of reducing the deformation of the coupling substrate 21 by the first region RE1 and the second region RE2 is remarkable.
Furthermore, as described above, the first region RE1 and the second region RE2 are aligned in a longitudinal direction of the pressure chamber C. Therefore, the supply communication flow path Ra and the nozzle communication flow path Na are aligned in the longitudinal direction of the pressure chamber C. Therefore, the ink can be supplied from the vicinity of one end of the pressure chamber C in the longitudinal direction through the supply communication flow path Ra and the supply port Sa, and ink can be discharged from the vicinity of the other end of the pressure chamber C in the longitudinal direction via the nozzle communication flow path Na and the discharge port Ve.
Further, as described above, the opening area of the supply port Sa is smaller than the opening area of the discharge port Ve. Therefore, the pressure applied to the ink in the pressure chamber C is hard to escape from the supply port Sa and is efficiently transmitted to the discharge port Ve.
Hereinafter, a second embodiment of the present disclosure will be described. In the embodiment illustrated below, elements having the same effects and functions as those of the first embodiment will be given the reference numerals used in the description of the first embodiment, and each of the detailed descriptions thereof will be appropriately omitted.
In the communication substrate 12A, each of the first region RE1 and the second region RE2 has a tapered portion 12a inclined toward the supply port Sa. As a result, the cross-sectional area of the supply communication flow path Ra becomes smaller toward the supply port Sa.
In the example illustrated in
Also according to the second embodiment as described above, it is possible to reduce the deterioration of the ejection characteristics due to the deformation of the coupling substrate 21. In the present embodiment, as described above, the tapered portion 12a that is inclined from each of the first region RE1 and the second region RE2 toward the supply port Sa is provided. Therefore, by reducing the retention of air bubbles in the vicinity of the supply port Sa, it is possible to suppress deterioration and fluctuation of the ejection characteristics. In addition, the area of the portion where the coupling substrate 21 is disposed in a single layer can be reduced. As a result, even though the coupling substrate 21 is formed of a material having a low Young's modulus with respect to the pressure generated in the pressure chamber C, the coupling substrate 21 does not act as unintended compliance and can avoid deterioration of the ejection characteristics. Further, the reliability of the head chip 10 can be improved.
Hereinafter, a third embodiment of the present disclosure will be described. In the embodiment illustrated below, elements having the same effects and functions as those of the first embodiment will be given the reference numerals used in the description of the first embodiment, and each of the detailed descriptions thereof will be appropriately omitted.
In the communication substrate 12B, the end of the supply communication flow path Ra in the Z1 direction extends in the W1 direction toward the pressure chamber C, and near the end of the supply communication flow path Ra in the W1 direction, the supply communication flow path Ra and the pressure chambers C communicate with each other via the supply port Sa. Here, the second region RE2 has a tapered portion 12b that is inclined toward the supply port Sa.
Also according to the above-described third embodiment, it is possible to reduce the deterioration of the ejection characteristics due to the deformation of the coupling substrate 21.
Hereinafter, a fourth embodiment of the present disclosure will be described. In the embodiment illustrated below, elements having the same effects and functions as those of the first embodiment will be given the reference numerals used in the description of the first embodiment, and each of the detailed descriptions thereof will be appropriately omitted.
The coupling substrate 21C has a shape in which the supply port Sa extends from a position where the supply port Sa overlaps the supply communication flow path Ra in a plan view to a position where the supply port Sa overlaps the pressure chamber C. As a result, the supply communication flow path Ra and the pressure chamber C communicate with each other via the supply port Sa. More specifically, the supply communication flow path Ra and the pressure chamber C communicate with each other through a gap formed between the communication substrate 12 and the pressure chamber substrate 13 by the supply port Sa. Further, since a flow path cross-sectional area by the supply port Sa is defined by the thickness of the coupling substrate 21C, the flow path resistance of the supply port Sa can be made higher than the flow path resistance of the discharge port Ve.
Also according to the above-described fourth embodiment, it is possible to reduce the deterioration of the ejection characteristics due to the deformation of the coupling substrate 21C. In the present embodiment, as described above, the supply communication flow path Ra and the pressure chamber C communicate with each other through the gap formed between the communication substrate 12 and the pressure chamber substrate 13 by the supply port Sa, and thus, it is possible to eliminate a portion where the coupling substrate 21C exists in a single layer near the supply port Sa. Therefore, deterioration of the ejection characteristics due to the coupling substrate 21C is suitably prevented.
The embodiments given as examples described above can be variously modified. Specific modified aspects that may be applied to the above-described embodiments are given as examples below. Two or more embodiments optionally selected from the following examples may be appropriately combined within a scope where the embodiments do not contradict each other.
In the above-described embodiments, the configuration in which the ink is circulated inside and outside the head chip is exemplified, but the configuration is not limited to this, and for example, a configuration in which the ink is circulated inside the head chip may be used. In addition, a configuration for circulating ink is adopted as needed and is not essential.
The above-described embodiments exemplify a configuration using different types of first ink and second ink. However, the configuration is not limited to this, and the number of types of ink used in the liquid ejecting head 150 may be 1 or may be equal to or greater than 3.
The form of each section of the ink flow path in the liquid ejecting head 150 is not limited to the above-mentioned form, and may be appropriately changed depending on, for example, disposition of the head chip 10. The holder 153 of each section constituting the flow path and the flow path structure 151 may be integrally configured.
The liquid ejecting apparatus 100 exemplified in each of the above-described embodiments can be adopted in various devices such as a facsimile machine and a copier, in addition to an apparatus dedicated to printing. However, the application of the liquid ejecting apparatus of the present disclosure is not limited to printing. For example, a liquid ejecting apparatus that ejects a solution of a coloring material is used as a manufacturing device for forming a color filter of a liquid crystal display device. Further, a liquid ejecting apparatus that ejects a solution of a conductive material is used as a manufacturing device for forming wiring or electrodes on a wiring substrate.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2022-042247 | Mar 2022 | JP | national |
